The fifth world.

Like, okay, I can handle some changes. It'd be nice to have a consistent number of legs, but switching from four in the morning to two in the afternoon -- it's not the worst thing ever. But having to walk on three legs in the evening -- that's just ridiculous. What kind of organism walks on an odd number of legs? It's so inconvenient, I can never keep my balance. I swear, whatever mf came up with this system must have had some serious complexes...