I'm using looting 3 in main-hand, looting 4 in off-hand, witches gem 3 on head, and difficulty 7, but I haven't had a single pigman head drop at my farm. I've killed many hundreds and normally I'd have several stacks of heads by now. Might it be safe to assume they are bugged?
I killed a few yesterday with bow & arrow and got a few heads. Not sure if that helps or there might be a problem still.
Tailchaser, I am wondering how much damage the pigmen have before you kill them. This makes a big difference. If you are doing as you say and you attack them with full damage to start with, they should be dropping a head about 1 for every 100 kills or better. I haven't had any problem with head drops recently. Except for those pesky mobs that I haven't figured out yet....Elder Guardian especially! (and Iron Golem)
Try difficulty 10 if you are in a safe area. I got many this way. Just be careful as they can teleport to you on this difficulty.
I never get heads from farms. I thought heads didn't drop when a mob is trapped and can't get to you. Does it not work that way? If you need some pigman heads let me know Tailchaser. I have more than enough, I'll share.
Difficulty 7 in the past has always given me plenty of heads. I've now noticed that I'm not getting any special emc drops from them, like torches or arrows or steak, etc. Maybe something bugged out because there are too many effects on the loot and the game defaults back to vanilla drops? Edit: I tried it without the extra loot modifiers, still nothing.
