Not the most off thing in Bionicle, but worth a mention: Kopaka Mata's shield. It has a bunch of big holes in it. That defeats the whole purpose of a shield. While quite a few shields in Bionicle prefer looking cool over practicality, Kopaka's shield is just an oddity. Seriously, did no one look at it and think "Hmm, wouldn't those gaps render having a shield pointless?"