Melee

Isaac stomping on a Slasher.

In the Dead Space series, Isaac Clarke, John Carver, Tim Caufman, Sam Ackerman, Gabe Weller, and Karrie Norton are capable of engaging Necromorphs in hand-to-hand combat by stomping or hitting with a currently equipped weapon or tool.

While both forms of melee are extremely ineffective in killing all but the weakest Necromorphs (such as Swarmers or the Pack) a well timed punch can buy the player some time by knocking enemies back, and Isaac can use his powerful stomp to smash containers, Necromorphs, and their limbs- both dead and alive.

Grappling

A grappling sequence begins when a Necromorph uses its signature grapple attack on the player character. This initiates a melee quicktime event: If the player is successful, Isaac will escape (albeit inevitably wounded in the clash) and, in the case of Feeders, Lurkers, Infectors, the Pack, Swarmers, the Creeper and Divider components, kill the Necromorph outright with a counterattack. However, Wasters, Pukers, Leapers, fully formed Dividers and Slashers will survive the encounter unless mortally wounded, and the player must be ready to continue the fight if they do happen to survive.

Tips

Dead Space (2008)

• In Dead Space (2008), Necromorphs' ability to foil Isaac's punches and stomps makes meleeing Necromorphs without the aid of Stasis ill-advised.
• If ammo is scarce, then the player can kill a Pregnant by applying Stasis to it and stomping its legs until it falls, at which point Stasis is reapplied and the player can stomp it to death.
• Melee can be used, if timed right, to stop a Slasher charging at you from doing harm. It does not need to do damage; blocked attacks provide the same result, effectively parrying the attack.
• The rate of attack (Swings and Stomps both) are a lot slower in Dead Space compared to Dead Space 2, leading to using melee effectively to dispatch enemies in Dead Space fairly ineffective compared to the second game, where the swings come fast after one another.

Dead Space 2

• While Isaac's melee range in Dead Space 2 is shorter than in Dead Space, Necromorphs will not block melee attacks, and punches can be aimed toward the head or legs.
• While a stomp deals more damage than a punch, a punch's sweeping motion allows it to hit two body parts or Necromorphs simultaneously.
• Continuing to tap the 'Stomp' button will let out an unending chain of skull-crushing stomps.
• While repeatedly stomping, one can hear Isaac loudly and bitterly cursing.

Dead Space: Extraction

• Melee in Extraction is executed via a Wii Remote swing, which deals negligible damage to Necromorphs and should only be used for solving puzzles, or as a last-ditch effort to finish off wounded attackers.
• While weak (and often futile), enemies struck by a melee swing will become briefly stunned, and spamming melee will stun-lock them indefinitely until they die or until the player stops attacking. This can, and should only be done, when the currently-equipped weapon is desperately in need of reload, as the player can reload while meleeing.

Dead Space (mobile)

• Vandal can utilize her Plasma Saw for a quick slash at any Necromorph within range. It is, however, relatively weak and does not deal reliable damage to anything besides a Slasher. A Necromorph hit by the saw will flinch back, however, giving the player room for a quick counterattack or simply slash the Necromorph into submission.
• It also cannot be used at will, the prompt for the saw slash only appears when an enemy is near.

Dead Space 3

• Standard Swing & Stomp attacks return for Dead Space 3, but their effectiveness has been reduced.  Notably, a successful melee strike will no longer guarantee knockback, often leading to an enemy charging right through your attack. Enemies also seem to have an increased resistance to simply being beaten to death & attempting this is a good way to get chopped to pieces.
• The Hydraulic Engine lower tool can be attached to any primary weapon, giving it a devastating melee attack as its secondary fire. One must be aware of the actual effect of the Hydraulic Engine when equipped, as its effectiveness is only active when aiming the weapon and using the tool. With the Conic Dispersal tool-tip and judicious use of stasis, the hydraulic hammer can kill Slashers, Leapers and Lurkers with ease.

Trivia

• From Dead Space 2 onwards, prolonged stomping causes Isaac to mumble curses and other phrases, such as "Die... Die!", "Shit!" and "Mother fucker!"
• The use of the Plasma Saw in most of the melee combat of Dead Space (mobile) makes it easier to the kill some lesser Necromorphs and allows Vandal to dismember them during counterattacks. The other two melee types are stomping on crawling Necromorphs and Vandal's spine-snapping, tentacle chopping, punch-it-across-the-room counterattack to a Lurker's jump.
• Dead Space 2 melee attacks are the most devastating in the entire series, as all Necromorphs make no attempts at blocking/evading Isaac or Gabe's punches, which, depending on the chosen difficulty, make extremely short work of even Enhanced Necromorphs.
• In Dead Space and Dead Space 2, Isaac's melee damage varies depending on which weapon he has on hand during the attack. A bash from a large Contact Beam deals a great deal more damage compared to a quick swing from a Plasma Cutter. By the time of Dead Space 3, however, all weapons deal the same damage when swung at a Necromorph.