All Invincibles: http://goo.gl/U3z43
So, please read the description for more info.
Spawning Omnd Omnd Ohk isn't actually that hard. Tedious, sure, but not hard. Head to Low Gut Rut, and kill savages, warriors and gunslingers until the badasses arrive.
As long as there's at least one witchdoctor, they'll (generally) start to evolve the badass savages. Damaging them can help a little. Sometimes, the witchdoctors will stop upgrading, either because they're lazy, or they insist on making tornados instead. Just quit and take another crack.
It took me 103 tries before I saw him at all. It's not guaranteed. Entirely random. I then got him 3 times in a row, during which he dropped 2 twisters.
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