First of all, you need the DLC Legacy of the First Blade - Episode 3: Bloodline installed.
Then, you need to purchase the Fury of the Bloodline ability (Tier 4 - Warrior Tree).
This ability works on animals. Especially wolves are ideal as they will not run away from you and will die in one hit. There is a sync point/viewpoint in Achaia called Watchtower. When you fast travel to this waypoint, there are 5 wolves waiting for you. They can't get to the branch you are standing on, so just kill one with the fury of the bloodline ability, hop on the branch and wait for it to recharge, the wolves will be waiting for you at the bottom. After all wolves are dead, you can just fast travel away and back and they should respawn. If not, just use the Dawn&Dusk ability to speed time couple times and then fast travel back.