PC Gamer’s guide says players should generally kill Xanthe rather than spare her after defeating her in The Cycle of Love quest. Sparing the ancient vampire makes the final assault on Griefberg Castle slightly easier, but allows her to continue sacrificing women to sustain her daughter, Chariklea.

An alliance removes Blood Guard enemies from the castle assault, lets Xanthe offer advice and avoids a short nightmare puzzle involving spectres. Killing her instead grants the Blood Surge ability if the player drinks her blood, although it requires a later decision over Chariklea’s fate: leaving her alone or ending her suffering.