Wall spikes were an environmental hazard that could be used to dispatch both human and vampire enemies in Legacy of Kain: Soul Reaver and Legacy of Kain: Defiance. Enemies thrown towards the spikes would be impaled and instantly killed.
Wall spikes were first introduced in Legacy of Kain: Soul Reaver as a hazardous element for vampires. Initially they were first observed in the Legacy of Kain: Soul Reaver prologue in the areas around the Sanctuary of the Clans, in a room where Raziel met the first fledgling Dumahim enemies and explained vampire weaknesses and combat tactics, with the wall spikes used to exploit the vampire weakness to impalement injuries.
In the early stages of Soul Reaver, Raziel was required to face an enemy in close combat until they were weakened enough to enter a stunned state, when they could be grappled, picked up and thrown directly onto the spikes, instantly killing them and releasing their Souls. After battling the Tomb Guardian in the chamber beneath the Tomb of the Sarafan in Tomb Of Sarafan (chapter), Raziel was able to gain a relic which enabled him to use Telekinetic force projectiles and from this point onward, Raziel was capable of using well aimed force bolt (or on occasion Glyphs) to catapult enemies into the spikes without the need to close in or enter melee combat.
Wall spikes returned in Legacy of Kain: Defiance, where Kain and Raziel were again able to use them to instantly dispatch enemies. The spikes were first seen and from the outset of Infiltrate the Stronghold and their usage would be demonstrated by Kain shortly after as he used Telekinesis to drag a Sarafan archer from a high platform onto wall spikes below. With the updated combat in Defiance, Raziel and Kain were no longer required to weaken or grapples their enemies in order to impale them, and by using regular telekinesis attack, they could hurl enemies onto spikes, killing them without physically touching them.