Uhhhh..... what?

Lol so here's the story... I've had this single player world going since the Monster pack was released. I havn't done anything to break it. Something I like to do it let it sit running while I sleep at night so things that require time get done quicker (like on a server). Some things I've done include my xp farm on most nights, let quarries run, things like that.

Last night, I set up a mana bean farm using golems. I decided to let that run overnight. Well, I woke up this morning, and saw the...

Uhhhh..... what?