bhahaha im the luckiest dude alive. i started from ratchet, killing all those patriarchs and all, got to the quilboars, and mass murdered again. five minutes in, i saw that lv. 15 elite pig, slaughtered it, and *beep* there it was.
it seems that normal deviate fish give you random buffs and debuffs (one put me to sleep for about 30 seconds). the cooked ones turn you into pirates. you can right-click on the pirate buff to cancel it, but it lasts an hour anyway.
imagine if we got everyone to morph into pirates. my god, how many "yarr!!!"s would there be??