Tuska Daemon-Killa

Tuska da "Daemon-Killa" is a Ork Warboss who lead an entire WAAAGH on a goddamn hilarious rampage through the Eye of Terror. He and his WAAAGH are known for being one of the few explicitly against Chaos, and being one of the most badass snippets of Ork fluff in all of Warhammer 40,000... And that's saying something.

The Beginning

Tuska was once a normal Warboss, like you and that git over yonder. He was rolling around the galaxy in his space hulk Gorejaw, minding their own business... until an unknown many-headed Greater Daemon snuck onboard and started rampaging through the Kroozer, killing anything and anyone in its way. Upon hearing the screams of his Boyz being massacred, Tuska went "ZOG ME, SOUNDS LIKE FUN!", rigged up his Power Klaw, and ran screaming towards the bridge. The resulting battle when he reached the bridge was spectacular, with Tuska nearly dying in the process. After that, Tuska discovered two things:

1. Daemon trophies are really fucking cool.
2. Daemons are big, killy, and a real fun scrap to get into.

So from that point foward, Tuska, now calling himself "Daemon-Killa", made an oath; to kill those squigy Deemuns and have the best damn time of his life while doing it. He then gathered all his Weirdboyz, and bolted straight for the Cadian Gate. WAAAGH Tuska had begun.

Prosan

When Tuska and his retinue reached the Cadian system, Imperial Command freaked the fuck out. With an armless superhuman and dozens of Chaos cults popping up everyday(as usual), the LAST thing Cadia wants to become like Armageddon with Orks crawling all over it. But to their confusion/relief, the Orks instead assaulted the nearby planet of Prosan. The reason for the confusion was that Prosan was literally just a rock of no strategic value; a hostile planet used by Cadian Guardsmen as training grounds. Still pissed-scared, however, the Imperial Navy intercepted them as the waves of Orks were being thrown at Prosan. The experienced regiments on the planet held the greenskins at bay, but they would soon be overwhelmed if the Orks kept coming.

But as suddenly as they arrived, Tuska and his Boyz picked up sticks and ran straight for the Eye of Terror, much to the ever-growing confusion of the Cadian High Command. As it turns out, Tuska was using Prosan as a warmup for his venture into the Eye of Terror. The Cadian System: one of the most active and heavily defended Imperial systems in the galaxy, was simply practice for Tuska and his Orks. OI! U MAD, KREED?!*BLAM!* HERESY!

On the flip side, Tuska would need all the practice he could fucking get.

Krumpin' Time

When Tuska plunged into the Eye, things went batshit real quick. The worlds they saw would've driven any human insane and gibbering dozens of times over... luckily, Orks don't stop to comprehend the Warp or boring shit like that. Because of that, WAAAGH Tuska plowed through several Daemon worlds. Tuska did not segregate about which of the Chaos Gods' domains he trespassed in; crushing crystal worlds made up of pure thought owned by Tzeench, to jungle worlds infested by temptresses of Slaanesh. This wasn't easy, however, as Tuska's forces slowly dwindled as he conquered various worlds. This didn't deter Tuska. He kept slaughtering every-goddamn-thing in his way.

This grand adventure would meet its end on a planet literally made of blood. When the Orks made planetfall, they were met with nothing. Enraged, Tuska shot at the bloody ground with his shoota, and was met with a shake of the planet. He looked at the ground, his Boyz, the ground, and then his Boyz again. He yelled out "FIRE EVERYTIN!'" All the Orks began firing everything they had at the ground. With a tremble, Bloodletters popped up from the surface and rampaged through the mobs of Boyz. All of a sudden, the Khornate Daemon Prince by the name of the Blood Prince (...original, I know), popped up and challenged Tuska.

Tuska and the Blood Prince dueled for hours as Tuska was repeatedly wounded and his Orks dwindled one by one. It climaxed when Tuska was pinned to the ground via a blade through his gut. The Blood Prince roared and proclaimed his victory over Tuska and his fellow Greenskins. Luckily, some of Tuska's Weirdboyz caused a distraction long enough for Tuska to pull one final, amazing act of defiance.

He reached up and (presumably) crushed both of the Blood Prince's daemonic balls with his Power Klaw, causing a squish loud enough to cause the Emprah to cringe slightly on the Golden Throne. The daemon squealed a high pitched scream similar to that of a Pretty Marine, and Tuska subsequently died from his injuries. TL;DR: It was FUCKING metal as FUCK, dude.

Tuska's story would've ended there if Khorne himself didn't witness these hilarious shenanigans caused by the Orks. Because of this, he resurrected Tuska and his WAAAGH for them to do battle with his champions and generals every day. With each dawn, Tuska and his Boyz would come back to life, fight and die, and the process would repeat. To anyone else, this would be a never ending hell of violence and dying... but to Tuska, he was loving it. He could live out his dreams of killing daemons for all eternity in the shadows of Khorne's Brass Citadel. Tuska had come home. TUSKA WILL RETURn, AND HE WILL STOMP DA ENTIRE GALAXIE!!! Which, is not an idle threat at all. Orks get bigger the more they fight,and Tuska and his band have been fighting and dying 24 hours a day, seven days a week, in the warp which is a temporal Möbius strip at the best of times. After all that fighting it would not be surprising if they were the size of Dreadnoughts. If for what ever reason they ever left the that demon world, maybe Khorne wanted them to krump somebody or he'll stop sending them bloodthirsters to fight him or something, well, Emperor help you.