Raining Blood - Disembodied Foot in the lowest level of Reaper's Cove (X:623 Y:559). Note that gaining skills appears to be random; I saved before eating the foot and gained the skill. I then saved again and reloaded to the previous save (before eating the foot), ate the foot and did not get the skill. This randomness happened at a earlier point in the game where I ate a limb and gained Tentacle Lash, then reloaded a previous save, ate that limb again and didn't get TL.
