The thing about ork warbosses in 40K crusade is this: they become unstoppable beasts. This is highly entertaining, of course, but they do have a way of making every game about themselves. Consequently, as the boss' Waaagh grows, I find myself using my other warboss models to represent his leff-tenunts. I could just say "here's a random boss," but it's way more fun to have a name and a personality. And so, one thing led to another and... well... ladies and gentlemen, for your consideration I present: the Boss-o-Matic 9000.
This extremely stupid series of random tables incorporate an ork name generator, a squig name generator, a gretchin name generator, and then goes waaaay further than necessary by generating a personality for your boss, including his quirks and hobbies.
Today, my brain worms iz green.
I've already had a fair bit of fun using this to generate a couple of leftenunts for my fellow Bunker dwellers to fight; generally if my opponent can take a boss out of play, then I have that player roll a dice. On a 4+, they've killed the boss, and I generate another. I'm generally just using an old copy of the Black Reach warboss for my generiboss, but it might be fun to use this as an excuse to paint up the newer warboss kit, since it it's really rather pretty.
If a boss survives his first battle, I start tracking his XP and taking out of action tests for him like normal. If he survives his next game, then you need a 5+ to kill him after taking him out. If he levels up to Battle Hardened or beyond, then you can only kill him on a 6+.
Hopefully in this way people will get the satisfaction of taking on repeat end-level bosses but actually killing them, and/or howling in frustration as they escape certain death.