Haegr the Mountain
"I should go get that back."
- – Haegr after launching his hammer over 50 feet to prove a point
Origin and aspects
Not much is known about this monster of a Space Wolf, however what we do know is that he went through the gates of Morkai as all other Space Wolves have before, and drank from the cup of Wulfen as is the rite of passage. It was later along in his initiation period that the Techpriests of the fang discovered some kind of fault or error in his system. While unlike those of genetic impurity, the fang skipped the paperwork and let him stay as his mutation wasn't as serious as you'd think with the wolves history of genetic mutation. Haegr is a big motherfucker, the tallest space wolf rivaling Leman Russ himself, also is his stomach, you ever see those Kirby gifs where he eats your mother's weight in food in one gulp? Haegr could eat about as much as that if he tried. His appetite is astronomical, once putting the fang almost into a food shortage. Due to this vast appetite, or another defect of this guy, is that he is fat as fuck, as in so fat that the tech priests had to custom build his armour to account for the sheer mass of his gut, this should be impossible especially for a space wolf due to their heightened metabolism allowing to digest almost any form of food or protein but not for this greedy bastard.
For whatever unknown reason Haegr was sent as an emissary of the space wolves to Terra as the Wolfblade, a unit of space wolves sent to guard and aid House Belisarius, a navigator house that are allied with the Space Wolves. It was here Haegr has spent possibly centuries of his life, missing and reminiscing his possible life of battle as he chows down on his 12th sheep sized meat pile.
TL;DR: He's a fat bastard who fights drunken master style with a thunderhammer. And not some prissy one-hander you'd use with a shield; no, the full blown "blacksmith anvil on a pole" heavy thunderhammer normally seen on Deathwatch Veterans. If you're gonna put him on the table, start with an ogryn mini and work your way from there.
How shit went sideways and how unlucky he is
Haegr later became close friends with another Wolfblade named Torin where they lived happily ever after... yeah.
Shit blew up very quickly when some prick named Ragnar Blackmane cocked up and lost the spear of their Primarch Leman Russ to the warp and ended up being sent to serve as a Wolfblade for a few centuries. The kid was new to Terran life and was very naive to Imperium politics. The moment Ragnar arrived things went tits up.
Firstly another Navigator house invaded, if you don't know the severity of this then allow us to explain: This is the equivalent of the entire European navy attacking the navy of the Americas, imagine the implications, without navigators or the Astronomican then the whole imperium would be fucked as they can't enter the warp and if they try then daemons of rape and paper cuts would swarm and devour the entire crew. Sort of. More accurately the Imperium would have to use numerous series of short Warp jumps to constantly make course corrections. OR the Imperium would have to become even more dominated by the Mechanicus by letting the AdMech handle the providing and maintenance of techno-horror Navigator analogues (that are probably better anyway, but still). Which would more or less make the Imperium the Mechanicus's slave.
So here we find that one house is slaughtering the other, mere months after this Ragnar fucker arrived. During the fighting Haegr is poisoned by an imperial assassin but luckily survives, and Ragnar goes werewolf on the assassin before it could reach the head of the house, resulting in saving the day. However the secret vaults were broken into and the ancient travelers inside were slaughtered resulting in a huge power vacuum. Luckily the house recovers and in the upcoming months of Haegr's life he forms some kind of bond between Ragnar and himself (no idea how, Ragnar is the source of nearly all his problems).
Later in his career Haegr is sent on a team with his friend Torin, Ragnar and about half a dozen other Wolfblades to the planet Hyades. Where things go from zero to "everything's fucked": all in all Chaos invades, literally sets the fucking world on fire, and because some chaos cunt had a grudge against Ragnar for foiling his plans time and time again, that's right, an entire fucking planet was set ablaze, thousands of both Dark Angels and Space Wolves were slaughtered along with the population of Hyades were murdered because of Ragnar! To their credit, when the two forces originally were fighting each other, they realized they were tricked and both groups of unimportant mooks redeemed themselves by putting the mortals together and using their own armored bodies as shields against a bombardment which killed the Astartes but the mortals were unharmed.
...but that's not all the shit that has happened to poor Haegr. Once he and the Wolfblades were back on Terra they were sent into the catacombs to suss out heretics and shit. On said mission they stumble upon a Psyker and his group of merry men and proceed to slaughter them while Torin kinda pissed off; in the battle Haegr is fucked to shit by the Psyker and had to have to escape, swim, and find aid to get sorta fixed while his entire left side had fused and burned into his armour exposing bone. All while having only Ragnar as company, so all in all Haegr has had some really bad luck that day (mainly in general ever since Ragnar arrived).
Feats and personality
Haegr is known for many things, for instance his sheer strength and size earning him the nickname the mountain, also is his appetite, capable of eating a tremendous amount of food or what ever is closest, he wields a mighty power hammer of which he uses to deadly effect with blinding speed which contrasts with his bulking frame, for range he uses dual bolters for mediocre effect and only uses when range is absolutely necessary and much prefers to cut the distance and get into the nitty gritty. Of which rather suits his personality, he's very boisterous and self representative, often referring to himself in third person and always talks far greater of himself and bulks up his image in events than he actually was, often challenging others to combat and trying to instigate a "beating" of which he often challenges his old friend Torin usually stating he would no doubt best him in combat.
Although his self image almost as big as his gut seems to take over his whole personality, he has been shown to care deeply about those who he calls friend and allies, at the death of one of the Wolfblade to a traitor and who breathed his last words in front of him, Haegr in boiling rage nearly murdered a squad of Dark Angels of whom were working in a temporary truce with the wolves, luckily Ragnar defused the scene before the truce was shattered and would have lead to many more deaths (so the big guy's got a heart after all).