Memories of Nyx
From Dawn of Corruption Wiki
Distant visions of pure Corruption echo within your soul.
How to Unlock
After choosing to unleash Nyx in Apothus' realm, continue to Feed the Chosen three times (this requires 9500 essence in total). During the next events choose to intervene and align with Nyx. Once reborn this ability will be given to your character.
Corruption + 20.0, Min Arousal + 10.0, Max Stamina + 10.0, Action Slots + 1.0, Growth Multiplier + 0.3, XP Multiplier + 0.3
If you win the fight with the guard you get the option to corrupt him. This gives you a scene where you attempt to do so, but get interrupted by Abel