I've killed both the Incontrevertible and the Disco Bison, although it took a few tries and LOT of looking around. I killed the incontrevertible in a Voinian Cruiser w/ maxed out phase turrets, bronev, and some dispy. rockets, plus a couple of CW escorts, an Iggy warship, an Aggy warship, and 2 Zidaras (I like variety in case you can't tell ;)). And against the Bison i used basically the same escorts only in a maxed-out CW. Disco Deep-fried Hamburger....hehehehe......And I've also met Furious n' Fiery or whatever, and I had a Zidara if i remember right. Launched my fighters and kicked his sorry little furious ass. The actual wEiRdIsT most StRaNgE ship i've come across is this M. Heavy Freighter with like 3 neutron turrets and a bundle of pursuit missiles. It was still just a heavy freighter, but it put up a good fight for my Arada which I had at the time....then i saw it again with a Zidara as my ship and killed it.
P.S. As an added bonus i happened to lose nearly ass my escorts in these battles, and had to go trhrough the tedious job of capuring new ones....Oh well. Feel sorry for me everyone! 
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Greetings from your friendly local cannibal, put in your town by the federal government to keep the human population in check.
If I were to face him now, I'd say he would probably beat me into the ground —Goku
(This message has been edited by ESPilot (edited 09-08-2001).)
When I destroyed him, I wasn't even intentionally trying to find him. I just happened to run a target scan in the strand worlds, and the Disco Bison happened to show up.