(1) Mutation fodder.
(2) If you build a deck around it, you can get a whole bunch of them together, then chimera it, then antimatter the chimera. This is not necessarily a good idea, but it's a positive use.
(3) Nightmaring them, kinda, but this is not really any different than nightmaring any creature the opponent can't/won't play, and still means you have to deal with the one you nightmared.
That's about the end of the list unless I'm missing some other bizarre outside case which I've forgotten about. Of course I haven't had much coffee yet so that's very possible.