Legacy of Kain: Soul Reaver is a 1999 action-adventure video game developed by Crystal Dynamics and published by Eidos Interactive for the PlayStation and Windows. A port to the Dreamcast developed by Nixxes Software was released in 2000, serving as Nixxes' first project. The second game in the Legacy of Kain series, Soul Reaver is the sequel to Blood Omen: Legacy of Kain. Soul Reaver was followed by three games, one of which, Soul Reaver 2, is a direct sequel.

Taking place 1500 years after the events of Blood Omen, Soul Reaver chronicles the journey of the vampire-turned-wraith Raziel, lieutenant to the vampire lord Kain. Raziel is killed by Kain, but is revived by The Elder God to become his "soul reaver" and to exact revenge. Raziel shares this title with Kain's sword, the Soul Reaver, which he acquires during the game.

Crystal Dynamics began development of the game in 1997, but a deteriorating relationship with Silicon Knights, who had developed Blood Omen, created legal problems. This and other delays forced material originally planned for Soul Reaver to be instead released with later games of the series. Soul Reaver gained critical acclaim. Critics praised it for its intriguing gothic story and high-quality graphics. However, the game was criticized for its simple and repetitive gameplay and an unsatisfying climax. By 2001, the game sold 1.5 million copies worldwide.

A remastered versions of Soul Reaver and its sequel were released on December 10, 2024, as Legacy of Kain: Soul Reaver 1 & 2 Remastered.

The player controls Raziel, a disfigured and ghostly vampire. The game is normally shown from a third-person perspective behind Raziel, but players can rotate the viewpoint around him. Gameplay relies largely on shifting between the material and spectral planes of existence to progress through areas. Although interaction with objects is limited in the spectral realm, this can be advantageous, because Raziel can phase through otherwise impassable gates there, and water is insubstantial, allowing him to walk on lakebeds; however, blocks, doors, and switches can be manipulated only in the physical realm. Many puzzles are based on the differences between the two realms; for example, platforms and environment features in one realm may change form to open new paths in the other. Block puzzles are also common and require the rotation, flipping, and moving of large blocks to progress, often with a time limit and while avoiding enemies.

Combat in Soul Reaver is a hack and slash system, involving the use of combinations of various different attacks before a finishing move. Raziel's enemies are grouped into humans, spectral creatures, and most commonly, vampires. Human enemies include peasants, vampire hunters and vampire worshippers. In the spectral realm, players fight minor enemies called Sluagh and the souls of dead vampires who have become wraiths. Each brood of vampire enemies has unique powers reminiscent of their clan leader. Human and spectral enemies can be killed with Raziel's claws or any weapon, but vampires must be bludgeoned into a stunned state and then destroyed by impaling them, setting them on fire, or tossing them into a hazard such as sunlight or water. When killed, enemies leave behind souls that replenish Raziel's health, which automatically decreases in the material realm and increases in the spectral. Possession of the Soul Reaver sword stops automatic degeneration of health in the physical realm, but Raziel loses the sword instantly if he sustains damage and can regain it only by restoring his health to full.

At first, Raziel can jump, glide using his torn wings, move blocks, and pick up and throw objects and enemies. Initially unarmed, he fights using his claws, but can alternatively use weapons such as rocks, torches, spears and staffs, and the Soul Reaver. Raziel can freely shift to the spectral realm, but can return to the material realm only through special portals when at full health. Raziel automatically shifts to the spectral realm if he runs out of health. As the game progresses, Raziel gains the powers of his clan brothers after defeating them and becomes able to phase through gates in the spectral realm and climb walls in the material realm. Initially vulnerable to water, he overcomes this weakness and learns to swim. He also gains the ability to constrict objects and enemies with a band of energy, although this feature was one of the few abilities not to feature in future games. Players can find an ancient relic that gives Raziel the power to fire bolts of telekinetic energy, which cause little damage by themselves but can knock enemies into hazards and push objects from a distance. Baptism in holy flame can transform the Soul Reaver into the Fire Reaver, which can set enemies aflame and adds fire to Raziel's telekinetic bolts. Players can also find magical glyphs that allow Raziel to expend magical energy to attack groups of enemies simultaneously. These glyphs typically involve vampire weaknesses such as sunlight, fire, water, or sound, as well as additions such as telekinetic force (available well before the normal telekinesis becomes available) and the causing of earthquakes to temporarily stun enemies. Glyphs are acquired through finding glyph altars, specific locations in Nosgoth where the skills can be learned, and solving a puzzle before being granted the magical ability. However, Raziel begins the game with access to the 'Shift' glyph, granting the ability to shift between the material and spectral planes, with no glyph altar necessary.

Soul Reaver takes place within the fictional world of Nosgoth, where the health of the land is tied to the nine Pillars of Nosgoth, and each pillar in turn is represented by a guardian. Before the events of Soul Reaver, the guardians became corrupt, and, after Kain killed eight of them, he discovered he was the final one. Refusing to sacrifice himself to restore the Pillars, he doomed Nosgoth to eternal decay and proceeded to raise his vampire lieutenants, including Raziel, to besiege the land. By the time of Soul Reaver's introduction, the vampires are now the land's dominant species and apex predators, the humans have been decimated, and the vampire tribes have each claimed a region of Nosgoth and turned their attention to internal matters. Unknown to the vampires, beneath Nosgoth lurks The Elder God, an ancient and powerful entity. The Elder God controls the Wheel of Fate, a cycle of reincarnation of souls that circle the Wheel in a loop of predestination; however, because vampires are immortal, their souls do not spin with the Wheel, causing the land to decay as the Wheel stalls. By the time that Raziel is revived centuries after the game's opening cinematic, Nosgoth is on the brink of collapse, little more than a wasteland wracked with cataclysms and earthquakes.