Haha, that reminds me of a story someone told me once.
They were creating an infantry training simulator, and they wanted to make the kangaroos on the ground scatter realistically when a helicopter flew over, so they re-used the same AI behavior they had previously created for infantry soldiers, and it worked beautifully . . . until the kangaroos popped their heads back up from behind a hill and started firing RPGs at the helicopters.
The best part is that they couldn't figure out why they were getting caught. Just imagine going through the code 100th time and you still can't find any errors. Later you realise that the bug was triggered by something completely different and absolutely ridiculous.
Maybe chickens can put the stats back in the game! =P
maybe that's why Fable had "kick the chicken" contests