Isaac Clarke

Isaac Clarke was a former ship systems engineer who worked for the Concordance Extraction Corporation and was the playable protagonist of the Dead Space franchise.

Prior to the Second Aegis VII Incident, he was part of an emergency maintenance team of the USG Kellion that was sent to the USG Ishimura to investigate and handle the ship's mysterious communications failure. Apparently the sole survivor of the incident, Isaac became stranded in space for a long period of time before he was rescued by an Earth Government ship.

For the next three years, Isaac was held in an asylum on Titan Station and was diagnosed with dementia resulting in haunting illusions that taunted him throughout the incident.

Years later, he still had the blueprint to destroy and create the Markers. However, he experienced the effects of dementia once again when he was exposed to one of the Brethren Moons.

Background

Childhood

Born on June 5, 2465, Isaac lived with his parents, Poul Clarke who was a ship designer and Octavia Clarke who was a Unitologist in the Northeastern American seaboard sector. As a child, Isaac lived most of his life with his mother as his father went on an extended mission before he could even get to know him.

Isaac took after his father and obtained an education in electrical and mechanical engineering. He was selected to attend a prominent engineering academy. Unfortunately, he was unable to afford the tuition fees as his mother who was a devout Unitologist squandered the family funds to purchase a vested-level title in the Church of Unitology. This led to his distrust and hatred for Unitologists and Unitology in general.

C.E.C. Career

Despite his financial difficulties, Isaac managed to graduate with high honors from a lesser college by becoming a ship systems engineer. Several years later, he signed up for the Merchant Marines division by allowing him to prove his abilities in original engineering situations to his superiors. Impressed by his progress, Isaac's superiors promoted Isaac to a position closer to the major shipping lines. At an unspecified time, Isaac worked on the Ishimura.^[1] Isaac lived with Nicole Brennan, but his career began to stagnate around the same time as her assignment to the Ishimura two years prior to its communications blackout.

The Emergency Mission to the USG Ishimura

In 2508, Isaac volunteered to be part of an emergency response unit that was attached to the USG Kellion. The crew was dispatched to the USG Ishimura. The ship was last reported orbiting Aegis VII on its illegal mission to crack the planet. Their mission was to investigate the distress signals^[2] that are sent by the ship and discover the reason behind the total communications blackout. Upon their arrival, the Kellion tried to hail the Ishimura to establish communications with the ship's crew, but was greeted with static messages. Unfortunately, as the Kellion tried to land on the Ishimura, the shuttle was severely damaged by a docking procedure malfunction and was forced to crash land into the landing bay. Due to the emergency crash land, the Kellion lost its port booster.

Shortly after disembarking from the damaged Kellion and noticing that the ship seemed to be deserted, the party was attacked by several unidentified entities in the Flight Lounge. These entities are revealed to be the Ishimura's deceased crew members that are being reanimated by a recombinant extraterrestrial infection known as Necromorphs. In the aftermath of the attack, only Isaac Clarke, the engineer, Computer Specialist Kendra Daniels and the team's commander, Zach Hammond survived.

Isaac was separated from the emergency response unit and avoided his pursuers by escaping in a nearby elevator. Still in touch with Kendra and Hammond via RIG, Isaac aided in the Ishimura’s repair by fulfilling numerous tasks across the ship. Despite the Necromorph opposition, an S.O.S. beacon was eventually placed on an asteroid that was undergoing ore extraction and purged from the mining hold. The signal attracted the attention of a military vessel called the USM Valor. However, the crew of the Valor was slaughtered shortly after they recovered an Ishimura escape pod that was containing a Slasher, trapped and unintentionally jettisoned from the ship's Bridge by Hammond.

With most of its crew dead or being transformed into Necromorphs, the Valor was left to drift out of control and subsequently sideswiped the Ishimura, violently crashing into it. A successful attempt to retrieve the Valor’s singularity core resulted in Hammond's death at the hands of an Enhanced Brute. Returning to the Ishimura, Isaac was contacted by Dr. Terrence Kyne who was a scientist who planned to return the Marker 3A to the colony below via the remaining shuttle.

After Isaac repaired the shuttle with the Valor’s singularity core and restored its navigation discs, Kyne was shot and killed by Kendra. She revealed herself to be a covert Earth Government agent and the entire conflict on Aegis VII was due to the CEC interference with the Marker. Shortly thereafter, she departed with the Marker.

Left for dead on the Ishimura, Isaac was saved by Nicole or so it seemed. After appearing, she compelled him to take the Marker back to Aegis VII, recalling the shuttle in the process. She forced Kendra to abandon the shuttle in an escape pod. Once he was on the devastated planet, Isaac finally succeeded in returning it to its pedestal. This resulted in a massive EMP that disabled the gravity tethers that are holding the chunk of Aegis VII above orbit causing it to fall back onto the planet that was pulled by it's gravity. Kendra appeared and removed the Marker from the pedestal with the intention to load it into the shuttle and return to Earth.

Before leaving Isaac to his fate, Kendra insisted that he went insane. She forced him to watch the conclusion of Nicole's video where he learned that she committed suicide during the outbreak on the ship. The Marker used Nicole's voice and appearance in his hallucinations. Despondent, Isaac returned to the shuttle pad in time to see the Hive Mind brutally kill Kendra. It attacked Isaac, but he defeated it.

After the engagement, Isaac piloted the Executive Shuttle just in time to escape from the colony as the tectonic load crashed down onto the planet. After his narrow escape, he reviewed Nicole's video one more time before being attacked by a hallucination of Nicole and presumably went insane.

Discovery

Shortly after the Second Aegis VII Incident, Isaac's shuttle was picked up by Recovery Patrol X22376 that was commanded by Captain Maxmillian Reinhardt and Xander Sklar.^[3]^[4]

After his rescue, Isaac was placed in a Stasis chamber and taken to Titan Station.^[5] There, Isaac, a scientist named Nolan Stross and several others spent the next three years subjected to experimentation by the Earth Government in Project Telomere. Isaac was confined to the Psych Ward in the Titan Memorial Medical Center and was diagnosed with dementia and post-traumatic stress disorder. Using the information that was imprinted on his mind by the Marker 3A, the memory suppressants are used in order to keep him and the other subjects in check as they manufactured the blueprint that allowed the Earth Government to build the Site 12 Marker.

Titan Station Outbreak

When a Necromorph infestation suddenly ravaged the Sprawl, Isaac woke up in a hospital and was freed by Franco Delille who was transformed into a Necromorph. After escaping from the overrun hospital, he was forced to make his way to a woman named Daina who was Franco's superior. As a result of Stasis and the memory suppressants, Isaac was unable to remember the past three years or how he ended up on the Sprawl. Daina claimed that she could cure Isaac's dementia which was allegedly killing him. Left with no choice, Isaac made his way to Daina by surviving the encounters with the Necromorphs and Earth Government troops that are ordered to kill him and led by Titan Station's Director Hans Tiedemann.

Along the way, as Isaac made his way closer to the Marker, he experienced more disturbing hallucinations from his dementia which are the apparitions of Nicole. Eventually, Isaac made his way through the Sprawl's Church of Unitology to Daina's location only to find out that she was a devout Unitologist fanatic that was sent to capture him. It became clear that as well as being forced to survive the Necromorph onslaught, Isaac was also caught in the middle of a growing conflict between the Earth Government and the Church of Unitology. EarthGov wanted him dead as they did not want him to destroy their Marker and the Church sought to possess Isaac because the Red Marker from the Second Aegis VII Incident left the knowledge of how to build the Markers in Isaac's mind. The Government was after that technology to study its effects and possibly develop it into a weapon while the Unitologists wished to build their own Markers in the interests of their faith.

Isaac was saved from capture by a Government gunship which killed all of the Unitologists that are present and forced Isaac into a maintenance hallway. There, Isaac was attacked by a massive Necromorph and as he escaped, he managed to destroy both his pursuers. Helpless with no contacts or a feasible escape plan, Isaac was contacted by a fellow test subject named Nolan Stross. Isaac encountered Stross several times before during which Stross revealed that he also encountered the Red Marker and was used to build new ones alongside Isaac.

Stross informed Isaac that there was a way to destroy the new Marker and guided him to its location. Along the way, Isaac encountered another survivor named Ellie Langford who rejected his offer of help and absconded. Some time later, Isaac was contacted by Ellie who found Stross on her way toward the Government Sector. Agreeing to work together and keep Stross alive, Isaac made his way to them. Despite several attempts by Director Tiedemann to thwart Isaac's efforts including forcibly separating a portion of the Sprawl, Isaac, Ellie and Stross are still able to progress.

During these events, Isaac discovered the recovered USG Ishimura which was almost fully repaired and was forced on board to use the gravity tethers to prevent the Government Sector from drifting away from the Sprawl. As Isaac traveled in the ship's halls, his hallucinations became more aggressive and frequent. Eventually, Stross’ already weak mental state collapsed and he attacked Ellie by removing one of her eyes. The insane Stross attacked Isaac who was forced to kill him. Making his way to Ellie through a mining area, the Nicole apparition attacked Isaac and demanded why he held on to her memory.

Isaac revealed that he was obsessed and riddled with guilt because he convinced her to board the Ishimura in the first place resulting in her death. He could not let her go because she was the only thing in the world that still mattered to him. The Nicole apparition was seemingly satisfied with this answer and revealed that "Acceptance" was the final step in Isaac's recovery. Isaac encountered Ellie who found a malfunctioning mobile mining drill inside a cavern. Isaac repaired it and Ellie piloted the mining drill while Isaac defended her from a horde of Necromorphs. The two drilled their way through an organic mass to the Government Sector where Ellie found a working gunship.

After a moment of contemplation, Isaac activated the gunship from outside, instructing Ellie to leave him and escape. Assuring the heartbroken Ellie that she would be safe, Isaac kept going to the Marker's location. As Nicole's illusion guided Isaac to the Marker, he remained uncertain about his subsequent actions. He was also forced to evade Tiedemann's personal troops by thwarting them by cutting the power to the sector and letting a horde of Necromorphs loose on the security force. Continuing his way to the Marker, Isaac came to a machine which was the subject of Stross’ mental state. The machine activated the parts of Isaac's brain where the Marker codes along with his lost memories are stored. At this period, the Necromorphs already reached the Marker in numbers and are sufficient to initiate a Convergence Event.

Hunted by the near-immortal Ubermorph, Isaac was able to make his way to the Marker where an angry and badly burned Tiedemann awaited him. After Isaac disarmed and killed Tiedemann, Nicole's apparition embraced him in front of the Marker and told him that he had to die as the Marker had to inherit all of its creators to be complete or become annihilated in the Convergence Event taking the whole station with it. Isaac entered a state of limbo which he mentally managed to break free of the Marker's influence while in reality, he was destroying the Marker.

As soon as Isaac regained his sanity, he resigned himself to his death. This was not to pass. Ellie was able to collect him with the gunship that Isaac sent her away in by bursting through the roof of the room that the Marker was kept in. As she navigated through the collapsing station, Isaac engaged the thrusters on his suit and boosted to the ship moments before the whole sector collapsed. Isaac who was haunted by his past expected all of this to be another cruel hallucination. Thankfully, all that sat beside him was a grateful Ellie.

In Hiding

After escaping from Titan Station, Isaac and Ellie went into hiding. They became romantically involved and took up residence in the Earthrise Apartments on Luna’s New Horizons Lunar Colony. Despite the fact that he freed himself from the Marker's mental grip, Isaac was still suffering from the effects of the Marker. His mind contained the secrets to create and destroy them. Isaac's inability to move on from the past eventually caused their relationship to deteriorate. Ellie ended their relationship and left Isaac.

Tau Volantis

On his own, Isaac continued to run from his past and was unaware about the escalation of the events between EarthGov and the Unitologists. He was still distraught over losing Ellie. One day without warning, his apartment was infiltrated. Isaac was attacked by Sergeant John Carver and Captain Robert Norton of the Earth Defense Force. Norton explained briefly that they needed him to destroy the Markers. Isaac initially refused. However, when he was told that Ellie went near Tau Volantis and was currently missing, he agreed to help Norton and Carver.

The New Horizons Lunar Colony was attacked by the Circle, a militant Unitologist sect that was under the leadership of Jacob Danik. Along the way, Isaac discovered that Danik worked to destroy EarthGov. Separated from Carver and Norton, Isaac was briefly captured by Danik who explained his intentions with the sabotage and murder of the civilians on the colony. He forced Isaac to watch the destruction of the colony's Marker test lab. After escaping from Danik and making his way through the infected city, Isaac escaped aboard the USM Eudora with Norton and Carver.

Upon arrival to Tau Volantis, the USM Eudora was bombarded by the remote mines in the debris field above the planet. Isaac quickly devised a plan to secure the pilots named Mark Rosen and Locke in the Eudora's escape module. He donned an EVA Suit and spacewalked to the module. He released it from the outside and the destruction of the Eudora sent it flying headlong into the debris field with he and Carver in close pursuit and Norton hanging on to the module and trying to regain control.

The crew managed to survive the hectic ordeal and board one of the abandoned ships called the CMS Roanoke. Isaac reunited with the crew of the Eudora and Ellie who was romantically involved with Norton. A technician named Jennifer Santos and a Marker operative named Austin Buckell found a shuttle in poor condition aboard the Terra Nova called the CMS Crozier.

Ellie reported that the Captain of the Roanoke wrote the Marker inscriptions on the wall of her room that may provide further leads. After investigating, Isaac deciphered the writing and revealed that the Captain discovered a Machine that could control the Markers and was obsessed with the phrase, "Turn it off". Ellie concluded that Tau Volantis was the Marker Homeworld. Norton spoke out urgently in favor of escaping to safety, but Isaac, Ellie and the Marker Ops team opted to continue the mission. They found a spare shuttle aboard the Terra Nova that was capable of descending to the planet's surface.

Norton claimed that Isaac was siding with Ellie because he still had feelings for her. He implored Isaac to abandon the mission for the sake of Ellie's safety by pointing out that there was little hope of success and a significant chance that they would all be killed, but Isaac contended that everyone would die if they gave up. Norton continued voicing his doubts about the mission. After the shuttle was secured, the team boarded and proceeded to enter the atmosphere of Tau Volantis.

During the landing sequence, the shuttle was knocked off course and crashed, killing Locke and Rosen and separating Isaac from the rest of the group. Isaac woke up on the frozen planet suffering from severe hypothermia, but warmed himself from the piles of the burning debris. Desperately searching through the wreckage of the shuttle, Isaac was greatly relieved to find a video that was recorded by Ellie and the other survivors. Isaac proceeded to follow their trail of flares into a building where he found Buckell lying on the floor.

After a brief talk, Buckell succumbed to his injuries. After some searching, Isaac found a RIG that was designed to withstand the freezing temperatures. Isaac caught up to Ellie and the team. In the meantime, Santos successfully recovered the fragments of the written information on an experiment that would help them. While attempting to reach the warehouse, they are attacked by Danik and his soldiers. Isaac was separated from the team, but managed to escape from the Unitologists and regroup in the warehouse.

In the warehouse was a giant frozen Necromorph known as the Nexus which contained the signals within its body that could be tracked back to the Machine. While attempting to thaw it and triangulate the signal, Isaac, Norton and Carver are ambushed and captured by Danik's soldiers. Danik revealed that it was Norton that led them to the planet under the pretense that he and the others would be given a shuttle if Isaac was surrendered to him. However, Danik reneged on their deal, intending to execute all of them. Isaac attacked Danik. He, Carver and Norton are able to fend the Circle off long enough to regain a mild advantage. However, the emergence of the Nexus altered their situation. Isaac was sucked into the belly of the beast and forced to shoot his way out. In the ensuing confusion, Norton became hostile and began blaming Isaac for all of their misfortunes.

Norton fired at Isaac and Carver which Isaac fired back in self-defense, shooting Norton in the head. After regrouping, Isaac tried to explain to Ellie what happened, but she refused to listen to him. Santos uncovered the information about a device that the researchers referred to as the Codex and a guide known as Rosetta in a lab on top of a nearby mountain. The group ascended the mountain, but a creature called the Snow Beast attacked when Santos was on the cargo cage. Carver severed the main cable, disconnecting it and sacrificing Santos to prevent the entire cliff side from collapsing.

Isaac eventually killed the Snow Beast by pulling it apart with the engine-powered harpoons and reunited with Ellie and Carver at the lab. As they explored the lab, they discovered that Rosetta was an alien dissected and carved up into separate sections. Rosetta possessed the information about the Codex, the Markers and the Convergence Event.

When all of the pieces of Rosetta are combined and scanned, Isaac was able to use the lab's equipment to experience Rosetta's memories: Rosetta was one of the planet's inhabitants that uncovered a Black Marker. This eventually led to a cataclysmic Necromorph infestation. After securing control over the sufficient biomass, the Convergence Event began. The event involved a massive transfer of organic matter, Necromorph mass and other materials into orbit along with the Marker to create a Brethren Moon which was the same Moon that was orbiting Tau Volantis.

Despite the imminent extinction of their species, the aliens used the last of their resources to construct an unimaginably powerful city-sized Machine which managed to quickly freeze the largely ocean world of Tau Volantis, halting the Convergence Event.

Isaac unknowingly revealed much of this in front of Danik who stole the Codex. He tried to stop them by using the decontamination protocol, but Danik escaped. The room filled with corrosive lethal gas which trapped Ellie and separated her from Isaac. Seeing no way out, Ellie tearfully told Isaac to close the doors so he and Carver could escape.

Enraged by the loss of Ellie, Isaac and Carver relentlessly pursued Danik by decimating the remaining Unitologist soldiers along the way. They recovered the Codex from Danik and descended to the buried alien city where they discovered how to use the Machine. At the Machine's core, Danik waited with Ellie who found a way to escape from the gas, but was captured by the Unitologist reinforcements. Danik threatened to kill Ellie unless Isaac gave him the Codex.

Carver who was believing in redemption grabbed the Codex from Isaac and threw it to Danik who let go of Ellie to catch it. Danik immediately used it to turn the Machine off, resuming the Convergence Event. The incomplete Brethren Moon that was free from the Machine's control descended toward Tau Volantis by instantly stripping the surface layers of the planet away under which the city and the Machine are buried. The ancient alien necropolis began to disintegrate as it ascended to be consumed.

Enraptured by his success, Danik was unceremoniously impaled and killed by a piece of falling debris. Realizing that there was no way to stop such an overwhelming force and escape safely, Isaac kissed Ellie goodbye and she escaped on a shuttle. Isaac and Carver worked together to fight their way through the crumbling flying city to the Codex. Being pulled up into the Moon-sized organism, they managed to reactivate the Machine and set it to its original function which stopped the Event and caused the Moon to crash into Tau Volantis along with the remains of the alien city.

Ellie grieved for Isaac, but took solace in realizing that her ship's instruments no longer detect the Marker signal. The Necromorph Moon was falling apart as it descended into and merged with the planet in a horrific cataclysm. Ellie setted a course for Earth and left the orbit of Tau Volantis.

Later, Isaac's voice was heard calling out for Ellie which was followed by the sound of Isaac's breathing apparatus.

Awakened

Isaac and Carver woke up underground after reactivating the Machine and destroying the Brethren Moon. After claiming a Unitologist ship, they escaped from the planet only to find out that they could not go back home without the ShockPoint Drive which happened to be on the Terra Nova which was the last surviving ship in the Sovereign Colonies Armed Forces flotilla.

The two defeated the newly formed Unitologist Cult and their so-called prophet and piloted the Terra Nova back to Earth only to discover that the other Brethren Moons already arrived. One of the Moons arose, causing both Isaac and Carver to suffer further damage from dementia and the screen cut to black. Their status is currently unknown.

Personality and traits

Even before the events of Dead Space, Isaac Clarke had strong resentment for the Unitologists which was an emotion that originated from the actions of his mother who spent all of the family funds on the religion. Following the events of Dead Space, this feeling would grow from distrust into hatred. Isaac enrolled in the electrical and mechanical engineering course, joined the Merchant Marines and focused on major shipping lines. Isaac tried to find out where his father was, but he was missing for quite some time and his personal files were kept classified by EarthGov. Isaac loved Nicole deeply as it was shown by his determination to find her among the infested USG Ishimura. Isaac was also heavily distraught after finding out that Nicole committed suicide during the initial Necromorph infestation and his visions up to that point were merely hallucinations that are caused by the Markers.

Even three years later, during the events on the Sprawl, Isaac found himself unable to let go of Nicole and was saddened and weakened by her continuous psychological presence. Fortunately, as Isaac traveled deeper into the Sprawl, he displayed strength against Nicole and was increasingly more willing to let go of her. Even so, Isaac was consumed with guilt over the death of Nicole as he encouraged her to take a post up on the USG Ishimura.

Due to his experiences on the USG Ishimura and the betrayal of Kendra, Isaac was understandably reluctant to trust the fellow survivors, particularly anyone associated with EarthGov or the Church of Unitology. However, he would still go out of his way to help others if the situation allowed for it.

Isaac's distrust of EarthGov began with Kendra's betrayal and their interests in producing the Red Markers for energy purposes. He was constantly hunted by the EarthGov forces while on Titan Station who are ordered to eliminate him along with the other subjects who are part of the Marker Project. Even after escaping from Titan Station, he was still hunted and was forced to go underground to avoid being captured. After being apprehended by Robert Norton and John Carver on the New Horizons Lunar Colony, Clarke refused to help them partly because they are EarthGov soldiers.

He was a selfless and determined individual as it was shown throughout the series. Some examples are him activating a gunship so Ellie could be rescued despite her protests (Not wanting her to end up like Nicole) and trying to save a fellow engineer (Santos) from a cable car under attack by a large Necromorph when doing so was dangerous to his own life, and when Carver cut the cable from the car and sent the engineer to her death, Isaac was angry and distraught. He even protected Carver from the Necromorphs during Carver's hallucination confrontations in the Marker Containment labs.

Skills & Abilities

As a C.E.C. engineer, Isaac is extremely resourceful. He displays his best abilities in hacking, repairing and dismantling electronic devices and has extensive knowledge of high-tech mining tools and other weapons which he uses to his advantage when in dangerous situations. An example of this came about during the Sprawl outbreak where he dismantled a Kinesis Therapy machine box in the hospital and removed its Kinesis Module for his own uses along with a Stasis Module some time later. He was also able to improvise a makeshift Plasma Cutter by using a flashlight and a surgical module when he tried to help a survivor. Isaac's occupation and duty of being an engineer for nearly 20 years also took a toll on his posture. Throughout the series, he walks and stands with a very noticeable hunch.

Isaac had no prior combat training before the events of Dead Space, being forced to defend himself against the Necromorphs with whatever that he could use as a weapon. Isaac learned the best ways of dealing with the Necromorphs through the logs that are left behind by the fallen survivors by even keeping one after his ordeal on Titan Station.

Though Isaac was not entirely immune to the Marker's signal, he had a high level of resistance toward some of its effects that it had on others. Though some were driven insane, homicidal or even suicidal by the Marker, Isaac only suffered from hallucinations. After escaping from Aegis VII's destruction and being apprehended by EarthGov, Isaac's exposure to the Red Marker's signal combined with his experiences made him catatonic, making a top candidate of a covert program on Titan Station to build a Marker. This program that was headed by Hans Tiedemann implanted the Marker symbols within Isaac's conscience so he and others could build another Marker. This in affect created the blueprint of a Red Marker within his head, making him a target of EarthGov. These symbols allowed Isaac to understand the messages from those affected by the Marker from which the average person wouldn't be able to understand.

Trivia

Isaac Clarke is voiced and modeled after Gunner Wright in Dead Space 2 and Dead Space 3.^[9] Prior to this in Dead Space, Isaac's face appeared somewhat more rounded along with a wider jawline and his hairline seemed to be receding. Although the player can clearly see Isaac's slightly battered face at the end of Dead Space, Isaac's visage can be glimpsed during the game's intro sequence. After the Kellion crash lands inside the Ishimura, the player can rotate the camera view around as Kendra and Hammond argued.
The name, "Isaac Clarke" pays homage to the world's renowned science fiction authors, Isaac Asimov and Arthur C. Clarke.
Likewise, the names of his parents, Octavia Clarke and Poul Clarke are likely tributes to the esteemed sci-fi writers named Octavia Butler and Poul Anderson respectively.
Even though Isaac is actually 49 years old, he is biologically 47 or 48 due to the effects of Stasis containment during his three years on the Sprawl.
Isaac seems to be very mentally resilient. He suffered from 3 betrayals, the deaths of several allies, 3 years of mental torture on the Sprawl, constant peril in each installment and he is still capable of communicating socially with ease. Except in Dead Space 3: Awakened where he lost his sanity and went against Carver (Who was also suffering from hallucinations) to try to slow him down because of the heavy dementia from the Brethren Moons.
According to the scales in the first Store that you came across in Dead Space 2, Isaac weighs 195lbs with his Patient Suit on. His weight rises from 195 to 255 pounds after wearing the CEC Engineering Suit.
Isaac's cameo in Dead Space 2: Severed is a wanted poster marking him as extremely dangerous.^[10]
In Dead Space, Isaac holds his Plasma Cutter with one hand standing still while aiming. However, in Dead Space 2 and Dead Space 3, he uses a two-handed grip.
In Dead Space 3, Isaac wears a flight jacket with a RIG attached, brown gloves and a shirt with an unknown logo with the words, "New Horizon" and "Hope". This is actually a stripped-down version of the Hacker Suit from Dead Space 2.
Nicole is not the only person that Isaac knew serving aboard the USG Ishimura. A comment in Isaac's "diary" (Accessed via the Objectives tab in the Menu) that appears while he was on the Mining Deck implied his familiarity with some of the mining crew or even implies that he was a crew member on the Ishimura at one time.^[11]
It is revealed in the Extraction comic that Isaac strongly dislikes the Unitologists.^[12]
In the PS3 version of Dead Space: Extraction, the trophy for completing the game on the Impossible difficulty is called "Isaac 2.0".
In Dead Space 2, Isaac canonically takes damage in only seven cases (The Slasher that pins him down in Chapter 1; being tossed out of the train car in Chapter 2; being slammed multiple times by the Tormenter in Chapter 5; being assaulted by a Drag Tentacle in Chapter 11; being thrown off the drill at the beginning of Chapter 13; being stabbed in the eye with the needle from the NoonTech Diagnostic Machine in Chapter 13 and being impaled twice from a Javelin Gun by Tiedemann in Chapter 15).
- Interestingly, Isaac's gameplay health status only goes down in the first and last instances.
Isaac is one of the only ten known survivors of a Necromorph outbreak with the others being Lexine Weller, Ellie Langford, Tyler Radikov, Alejandro Borges, John Carver, Robert Norton, Isabel Cho, Nicolas Kuttner and Nolan Stross.
- Isaac and Lexine Weller are the only two characters known to have survived both the events on Aegis VII and those on Titan Station.
- Isaac is the only character to survive the events of all three major Necromorph outbreaks and is also the character responsible for stopping all three outbreaks.
Isaac has been likened to the character named Ellen Ripley from the Alien movies due to his surviving the outbreak despite a non-military background as well as the fact that he becomes a source of information on the creatures similar to Ripley.
Isaac is a playable character in the European "Death Edition" of Dante's Inferno.^[13]

Additionally, Isaac is a playable character in the Skate 3 Free Skate Mode with the code, "deadspacetoo".
- As part of the marketing promotion for Dead Space 2, Isaac Clarke is also available in Dragon Age II. The players could access the exclusive Ser Isaac's armor by using a one-time activation code supplied with Dead Space 2. This ended on March 31, 2012.^[14]
- He is also a playable character in the game, PlayStation All-Stars Battle Royale with his default appearance which was the Arctic Survival Suit. His rival in the game is Zeus from the God of War franchise.
- Isaac was also planned to be featured in MySims Agents, but was removed before it was published as it was said by the MySims Agents concept artist named Genevieve Tsai, but there is still an Isaac Clarke costume that you can dress your character in. Isaac Clarke appeared in MySims SkyHeroes.^{[citation needed]}
Despite the symptoms in the other victims and hospital reports that are detailing Isaac's violent dementia, Isaac keeps his alleged insanity in check with proficiency over the game. Whether seeming relatively sound in the face of hallucinations or proving reliable on his own, Isaac's only real moments where one could question his mental health were during Nicole's several attempts to make him commit suicide. While this seems somewhat monumental that was compared to the barely coherent Nolan Stross or his own hospital supervisor, Isaac comes across as fairly sound minded with the possible exception being in Dead Space 3: Awakened when he stalls Carver due to the heavy dementia that he and Carver underwent from the Brethren Moons.
Throughout the series, Isaac shows unusual amounts of physical strength such as being able to dismember the Necromorphs with one or two swings with a weapon or a stomping on them. This is also exemplified when he effortlessly wields the heavier tools such as the Line Gun which weighs sixty pounds according to its bio-card.
At the beginning of the Awakened DLC, Isaac's left eye is no longer swollen from the explosion that he took earlier. Also, Isaac's suit still had its helmet intact, despite him ripping it clean off his face prior to the battle with the Moon. It is unknown how his suit was suddenly repaired without a Suit Kiosk and also how his wounds healed so quickly though this could simply be an oversight from the developers.
Isaac seems to be resistant to many forms of damage that would normally incapacitate or kill a human. He can survive falls and otherwise fatal stabbings from the Necromorphs such as in the beginning of Dead Space 2 when he survives multiple stabbings from a Slasher while being pinned down. Near the end of the game, Isaac also survives taking a Javelin spear in the shoulder and another spear in his left hand from Hans Tiedemann before killing him. In Dead Space 3, he could survive multiple fatal gunshots as well as being thrown off a cliff.
Daina Le Guin, Ellie Langford and Nicole Brennan are the only three people that Isaac refers to by their first names.
Isaac and John Carver's masks are available in the game, Army Of Two: The Devil's Cartel as one of the choices for the player's mask. Both franchises are published by Electronic Arts.

Quotes

Dead Space

"Grunt."

—Isaac, in Dead Space

Dead Space 2

"You're a Unitologist? Of course you are. Why did I trust you?!"

—Isaac, in Chapter 5

"Whoa—Hey, hey!"

—Isaac after dodging a Plasma Cutter shot

"You stay back! You wanna talk? You talk from there. And don’t say you’re here to help. The last person who said that tried to kill me"

—Ellie

"Hey, take it easy! I-I’m not gonna hurt you."

—Isaac

"Yeah… you got that right. You try it, and you’re dead"

—Ellie, in Chapter 6

"Are you insane…?! You cut off power to life support! There may be other survivors over here—!"

—Isaac to Tiedemann in Chapter 6

"Ellie, I ran into a snag—it looks like the docking pod that runs to the Solar Array is floating at the bottom of the shaft."

—Isaac upon encountering the disabled docking pod

"That figures."

—Ellie

"Ah, don’t worry. I can fix this. I’m heading outside to have a look"

—Isaac, Chapter 7

"Ellie, come in!"

—Isaac on the Solar Array

"Isaac! We have to cross to the Government Sector before they cut us off! You’ll never make it back here in time—!"

—Ellie

"I’ll be there! I’ll be there!"

—Isaac, before the HALO jump in Chapter 7

"Isaac, no! This is a really bad idea!"

—Ellie after Tiedemann blocks them from getting back to the Sprawl

"Stick around. I’m full of bad ideas."

—Isaac, in Chapter 9

"Yours is the last body to be reborn! The makers must be absorbed! "

—Nicole

"The Makers? You mean me? But Stross said we could destroy The Marker! "

—Isaac

"Not if we consume you first! "

—Nicole

"Goddammit, I trusted you! Fuck you, and fuck your Marker!"

—Isaac to "Nicole", in Chapter 15

Dead Space 3

"I don’t have a lot of time, so I’ll make this brief. I understand that you’re something of an expert on Markers. You created one—"

—Norton after finding Isaac

"I didn’t make shit! Your government made me!"

—Isaac while held in place by Carver

"—And you destroyed two. Which is why we’re here: we’ve got a job for you"

—Norton

"No. No! I’m done with that. You find somebody else for your suicide mission!"

—Isaac

"We did. And before we lost contact with her… She told us to find you."

—Norton in Chapter 1: Rude Awakening

"We each lost a part of ourselves during that nightmare on the Titan Sprawl. For Ellie it was her eye. Luckily, we found a replacement we could afford. Even though the color doesn’t quite match, at least she can feel whole again. Me. I lost a part of my soul. And there’s not a damn thing I can do to buy that back. I guess, ultimately, that’s why she left. People want things they can fix and I’m permanently broken."

—Isaac in a text log.

"Isaac! Carver! Goddammit, give me a hand here!"

—Norton

"Here! Grab some of that paneling, and seal up that doorway!"

—Isaac

"Since when’re you givin’ the orders?!"

—Norton

"Since nobody else has a fuckin’ plan! Look, I'll explain as I go!"

—Isaac, in Chapter 2: On Your Own

"Hey, I paid my dues! Or don’t you think I’m fucked up enough already?"

—Isaac after discovering the instructions to turn off the Machine

"Isaac, this is do-or-die! We’re stuck without your help!... Are you with me?"

—Ellie

"...doesn’t look like I have a choice."

—Isaac, in Chapter 4: History's Ember

"I’m reading a lockdown. Are you all right, Isaac?""

—Buckell

"No, not really! I’m locked in!"

—Isaac

"Well, there must be an override on one of the walls."

—Buckell

"Okay. I’ll look once I’m not being—stabbed in the face!'"

—Isaac, in Chapter 5: Expect Delays

"What do you think is worse, Buckell? Dying along with everyone else or being the only one who survives?"

—Isaac after cutting the power from Environmental

"It’s not the dying that scares me. It’s not making a difference before I do.'"

—Buckell

"Let’s get one thing straight, Clarke: we came to this frozen shithole to stop the Markers, and nothing—not you, or your obsession with Ellie—is gonna get in my way. You got that?"

—Carver

"I know why I’m doin’ this. Do you?'"

—Isaac, Chapter 9: Onward

"Ellie! I’m trapped and the drill is trying to kill me!"

—Isaac as the drill sequence begins (Single player)

"Now what?!"

—Isaac

"'You're the rocket scientist; you tell me!"

—Carver

"Hey, I work on ships, not—giant drills! Just—look for an override!"

—Isaac

"What the fuck is that?!'"

—Carver, during the drill sequence (Co-Op)

"Wait, you're not thinking we should mess with this sterilization system, are you?"

—Carver

"Mmmaybe?"

—Isaac

"Isaac, it's gas that eats your face."

—Carver

"Come on, what's the worst that can happen?"

—Isaac

"It's gas that eats your face!"

—Isaac and Carver proceeding to the sterilization fuse box (Co-Op)

"Hey, looks like we're stuck in here."

—Carver

"Come on look, it's working!"

—Isaac

"Yeah! This thing is airtight, right?"

—Carver

"Uh, yes?"

—Isaac

"Oh shit."

—Carver

"Come on. Let's check it out."

—Isaac

"Mmm hmm. You go first."

—Carver and Isaac using the sterilization system (Co-Op)

"Well, that sounds familiar. At least they didn't poke her eye out."

—Isaac, after hearing how the Codex codes were "lifted" from Rosetta

"Oh no... no... We've got it all wrong... This isn't the Marker home world! The aliens, they... they found the Markers, just like us - and it spread! It consumed them, it... it pulled their bodies into the sky to form the final stage... Oh my god! The moon... The Moon is the source of the Marker Signal, not the Machine! The Moon is Convergence! The aliens, they... they built the Machine to freeze the planet - to keep the Moon from becoming whole!"

—Isaac, realizing the truth about the Markers, Tau Volantis and the Brethren Moons

"Good men mean well. We just don't always end up doing well."

—Isaac to Carver after entering the Alien City

"Ellie, I turned my back on the world because I was afraid of what needed to be done. Ellie, I'm not afraid anymore. There's a shuttle over there. I want you to take it and head for home. Don't come back for me! We both know I'm not coming home! Go!"

—Isaac to Ellie before the final sequence begins

"You can't have us."

—Isaac to the Brethren Moon

"...but Earth... gets a tomorrow."

—Isaac before reactivating the Machine and killing the Brethren Moon