Hand of Fate 2

You will need Lord Veles as your companion, obviously.

Veles feasts on blood; either yours (which can be donated at camp at a cost of your own life) or that of your opponents in combat. Perform a successful knockdown on your opponent, but don't finish them off with Left Trigger-Veles usually then finishes them with a pounce attack, and visibly feasts. Note: he does not appear interested in all foes-I am yet to see him feast on a blighted opponent for example.

Choose 'Talk to Veles' at camp to monitor how much more 'hunger' needs to be satisfied. When his hunger is sated his companion card picture in the bottom left hand corner of your screen is transformed, and he will perform 'Blood Madness' attacks in your next combat experience. 8 such combats later this achievement should unlock.