Feral Blood

From AoCWiki

Feral Blood is a Tradeskill Resource used in the Tier I Alchemy recipes for the potions [Bloodslurry Brew], [Rageshine Tonic], and [Mindcurdle Infusion]. Feral Blood cannot be purchased from vendors, but instead must be obtained from drops.

Feral Blood is known to drop from alchemist's caches dropped by various human mobs of level 40 and up, as well as from felines of the appropriate levels.