Claws were first able to be utilized as a weapon in Legacy of Kain: Soul Reaver (the first game in the series to allow the protagonist to be 'unarmed'). Raziel was able to extensively use his claws against enemies in Combat (see also: Combat (Soul Reaver)), where claws were faster than other weapons, but lacked much of the power. Raziel's claws, whilst allowing Raziel to perform several combos and effectively 'stun' a Vampire, were not powerful enough to finish them outright - instead Raziel had to take advantage of the surrounding environment to kill Vampires (using one of the 'finishing moves'), or alternatively impale the vampire using a Spear or other weapons. Raziel's claws were insufficient to permanently cleave and impale a vampire in themselves[Soul Reaver].
Claws returned inSoul Reaver 2, once again utilised as Raziel's default weapon whilst unarmed.[Soul Reaver 2 manual][Soul Reaver 2 strategy guide (Prima)] Like their appearance in Soul Reaver, they were the quickest but also the weakest of the weapons at Raziel's disposal. Raziel could use claws extensively in combat against enemies (see also: Combat (Soul Reaver 2)) if he was not armed with any of the more powerful weapons. Unlike their use in Soul Reaver, claws were now powerful enough to penetrate and 'impale' an enemy (as he mostly fights humans, rather than vampires) enabling Raziel to execute a 'fatal blow' when the enemy was stunned, by ripping out their heart (possibly a nod to the fate of Janos Audron later in the story)[Soul Reaver 2].
In addition Kain was able to use his claws to attack enemies using three of his dark gifts; Fury and Berserk both used his claws into striking attacks, as well as the MistDark Gift's Stealth Kill ability, which used Kain's claws to rip out an enemies heart (and twist their neck)[Blood Omen 2].
Vampire claws close-up
Gloved Vampire Claws Close-up
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Apocrypha[]
In Nosgoth, the vampires of the mid-events of Soul Reaver battling Humans in the War for Nosgoth used claws as their primary weapons, using them extensively to melee opponents from close-range.
Notes[]
Claws are only used as a weapon in games which allow the protagonist to drop, break or otherwise lose their weapons; in both Blood Omen[Blood Omen] and Defiance[Defiance], the protagonist cannot lose their weapons.
Claws are implied to be a by-product of Vampires long lifespans, probably developing from Human nails - it is not revealed however, how long this change takes and this may be an alternative reason for Kain only wielding weapons in Blood Omen, as his claws were yet to develop.[3] Many other species, including the Hylden, Sluagh, Shades, Mutants, Poltergeists, Tentacles, Demons, Werewolves and many Animals have also developed claws.