Talk:Update 0.16.0/@comment-26276294-20160923155022/@comment-28757532-20160923202235

Wither skeletons are 2 and 1/2 blocks tall, so they won't spawn in 2-block tall spaces, maybe that's the problem. There's a 1/400 chance that they'll drop their skull, but you can use alooting sword to get them more often or a charged creeper to make them drop it every time.