So, I'm just starting to make some leather, and I ended up diluting my tanning fluid too much (it's at 2.5%). I killed two beavers and used their brains, but since I wanted to try to tan 4 hides, I added two additional buckets of water. Unfortunately, the fluid is not too dilute for any progress to be made.
What's the best source of brains? I'm at 25 humours and I was a little bit leery of trying to take on a deer I just saw walking by. Would I be able to kill a deer at my current level, or should I stick to searching for elusive beavers?