Defiance continues the journey of Kain and Raziel. After having Raziel killed to be revived by the Elder God as a wraith during the events of Legacy of Kain: Soul Reaver, Kain travels backwards through time and is followed by Raziel into Nosgoth's past, uncovering the conspiratorial events that led to the land being doomed to an eternity of corruption. After establishing his free will by refusing to kill Kain when prophesied, Raziel discovers that Moebius the Time Streamer had originally manipulated Kain into igniting a genocidal war against Vampires until he was the last of his kind. In manipulating Raziel who has free will and thus whose decisions and actions cannot be foreseen by Moebius, Kain hopes to find a way to undo the consequences of his actions and restore Nosgoth to its former glory.
While tying up a lot of loose ends, and arguably ending what can been described as the Soul Reaver Story Arc, Defiance would also end on a Cliffhanger for the series as a whole, leaving the story in a bit of limbo, since no further installments has been made since. It is worth noting that two serious attempts at a proper sixth installment in series were in development at various times. The first, The Lost Prophecy, was only in pre-production for about mere three months before being cancelled in 2004. The second, Dead Sun, was in development between 2010 to 2012, before it also was cancelled. These two projects were not general public knowledge at the time they were in development, their existence first being broadly revealed through leaks in 2013. Another game, though not proper installment in the series, Nosgoth (suspected by some to originally have been the multiplayer component of Dead Sun), was released as an open beta in January 2015, but was eventually also announced cancelled in April 2016, and shut down in May the same year.
Legacy of Kain: Defiance contains examples of the following tropes:
- And Show It to You: At the end of their fight in Avernus Cathedral, Raziel rips Kain's heart out.
- Art Evolution: Unlike previous games, where Raziel's version of the Reaver was simply a Blade Below the Shoulder, here, it's a complete spectral sword with crossguards and a hilt that Raziel holds. This was the intended design all along, but graphical limitations of the time prevented it.
- Bittersweet Ending: In the end, Kain is purified of the corruption and can now see the Elder God, recognizing it for what it is and leaving it under a mountain of rubble, and is prepared to finally put an end to the Hylden's plans. But at the cost of Raziel now being trapped within the Soul Reaver, something that Kain had made every effort he could to prevent. While a cliffhanger, it's still the most uplifting ending in the series, apart from the non-canon good ending in Blood Omen, which later games revealed would have really been a massive Downer Ending.
- Bootstrapped Leitmotif: Information Society's "Ozar Midrashim", the main theme of Legacy of Kain: Soul Reaver, is used to give Raziel a Theme Music Power-Up during his duel with Kain in the Avernus Cathedral.
- Chekhov's Boomerang: Raziel's mentioning he was imprisoned in the Spectral Realm for 500 years at the beginning of Defiance means this puts him exactly on course with the timeline of the original Blood Omen, explaining how he is able to meet with Ariel's spirit and Vorador. Later on, Raziel and Janos watch the pillars shatter perfectly in-time with the events of Blood Omen, and thus with his seal weakened the Hylden Lord possesses Janos.
- Chekhov's Skill: Possessing corpses in Defiance mostly serves as an alternative gameplay mechanic for Raziel to shift realms with the portals closed off to him. Until he uses Moebius' corpse in the climax to trick Kain into impaling him with the Soul Reaver.
- Color-Coded Characters: Raziel's color motif is blue and green, Kain's is orange and red.
- Dueling Player Characters: The game has a duel between Kain and Raziel, where the player must control Kain for the first portion of the fight, then control switches to Raziel halfway through.
- Do Not Go Gentle: Vorador is captured offscreen by Moebius' men while Raziel is at Avernus Cathedral, but not without, in Moebius' own words, "a considerable price in blood."
- Either/Or Prophecy: In Defiance, the Ancients and Hylden will each have a champion fight on their behalf, but the murals depicting their battle leaves it uncertain who will win. It turns out that Raziel is both champions—he's the Hylden Champion by way of giving them the means to free themselves, and he's the Ancient Champion by entrusting Kain with the means to destroy the Elder God. Ergo, by sacrificing himself, the two "champions" effectively kill each other.
- Elemental Powers: Kain and Raziel both receive elemental add-ons to their respective versions of the Reaver.
- Raziel's array goes Dark, Light, Fire, Air, Water, Earth, and Spirit and he can always switch between any of them at will while in the Material Realm.
- Kain's add-ons also have Fire and Lightning elements, in addition to the more esoteric Balance, Dimension, and Time modes. It was intended for Fire and Lightning to be called Conflict and Energy — Balance, Conflict, Energy, Dimension, and Time make up five of the nine Pillars of Nosgoth.
- Flash Step: Once Kain gains the Dimension portion of the Balance Emblem, His special attack is him repetedly doing this between enemies while hacking at them.
- Hate Plague: The Fire portion of the Balance Emblem causes this temporarily as it's special.
- Heel–Face Turn: Implied at the end; Raziel purifies Kain's corruption at the end, and presumably purifies the insanity wrought upon him by Nupraptor prior to the events of Blood Omen.
- Hope Is Scary: Kain ends the game expressing this very sentiment:Kain: Most ironic of all was the last gift that Raziel had given me: More powerful than the sword that now held his soul, more acute even than the vision his sacrifice had accorded me. The first, bitter taste of that terrible illusion - Hope.
- Jerkass Has a Point: At the beginning of the game, Raziel is trapped in the Underworld with the Elder God, repeatedly refusing to do his will under the belief that the Elder is nothing but a parasitic false god. The Elder, however, quickly deduces that part of the reason for Raziel's refusal to leave is out of fear of his destiny; to become the soul-stealing entity trapped within the Soul Reaver. Raziel admits to himself that the Elder isn't wrong, and ultimately decides to find a way to avoid said destiny rather than cower from it.
- No-Sell: Moebius's vampire-repelling magical staff has absolutely no effect on Kain after his heart is ripped out.
- Offscreen Moment of Awesome: Vorador is captured by Moebius' men while Raziel is investigating Avernus Cathedral, but when Raziel returns, he's informed that Vorador didn't go down without a fight.Moebius: We have him. But not without a considerable price in blood.
Raziel: That will have pleased him.
- Possessing a Dead Body: Raziel loses the ability to use conduits between the spectral and material worlds from previous games, but gets around this by learning to project his spectral form into human corpses. At the climax of the game, he uses this to trick Kain into impaling him on the Reaver, which he needed to happen to heal Kain but which Kain would have been unwilling to do, by possessing Moebius' recently-slain body, making Kain think the Time Streamer has returned to life again already before Raziel's wraith form reshapes it.
- Revision: The climax of this game reveals Kain's motivations for ordering Raziel's execution in Soul Reaver go far deeper than petty jealousy. The visions within the Chronoplast informed him of Raziel's future, and in executing Raziel and ensuring his resurrection as a wraith, he created a creature that truly possesses free will and thus was Immune to Fate, a key factor in his ultimate goal to restore Nosgoth.
- Sense-Impaired Monster: The "god" Hash'a'gik is a gigantic batlike monstrosity with useless vestigial eyes but a highly-developed sense of smell and even sharper hearing to compensate. Worse still, he also possesses telekinetic powers. Fortunately, the cult that's simultaneously worshipping him and keeping him captive has set up large gongs around his prison, allowing them to overwhelm Hash'a'gik with sound; Raziel can use these to his advantage over the course of the boss battle.
- Transformation of the Possessed: Raziel is forced to possess corpses as an alternate means of entering the Material Realm after the Elder God closes off the portals. Each time, he shifts the corpse's flesh into his own form. The brief delay that this takes to happen allows him to trick Kain into impaling him on the Reaver when he possesses the corpse of Moebius.
- Where It All Began: Of a sort. After spending previous games seeing the various stages of Nosgoth's history, as well as its possible futures, Defiance marks a return to the era of Blood Omen, which it happens concurrently with.
- You Can't Fight Fate: Deconstructed and examined. Raziel firmly believes that doing anything might result in him becoming the Soul Reaver as his destiny, until it comes to light that he is Immune to Fate; in an otherwise immutable logic of time, he's the walking paradox that can very well Screw Destiny. In the end, Raziel does give in to his fate to become the fully-complete Soul Reaver — by screwing destiny at the same time he's fulfilling it, as he gives Kain the means to harness the weapon against the Elder God and cures him of his insanity in the process, changing an assured Stable Time Loop into an unforeseen path with a dead Moebius and the opportunity to truly save Nosgoth from its bigger threats once and for all.