Beast of Nurgle
Take a slug. Now give it two big stompy feet. Now add a big leering toothy humanoid face on top of it. Make it diseased and a lumbering sack of all the worst plagues/sores/open wounds you have ever seen. Make it smell like the worst toilet you've ever been in and congratulations, you got the barest idea of what a Beast of Nurgle (or Slime Hound) must be like in person.
Oh but this great big nasty slime bag isn't evil. No, it just wants hugs!
A truly terrifying daemon created to horrify you in a way you didn't think possible, the Beast of Nurgle represents all the joy and happiness Nurgle feels in his big blackened heart. The Beast has the personality of a playful puppy and just loves making friends. Look at it slobbering towards you, it doesn't want to kill you. No it just wants to lick you all over with that pus weeping poisonous tongue it has.
While it wants playmates, those new friends of its never survive long, either crushed under its hideous weight or killed by the lethal viruses and poisons that make up its body. Upset that their new friends stop moving after a while, the Beasts set off to find someone new to play with, already having forgotten about the crushed pulp it was just slobbering over.
Oh, and sometimes Beasts of Nurgle who get banished back to the warp start to fester in their resentment, metamorphosing into vicious, cruel, bitter fly-daemons who love to suck people's heads clean off their shoulders, or swallow them whole and condemn them to an eternity festering in their stinking guts.
Truly Nurgle is a sick old bastard.
The 8th Edition Death Guard Codex has an illustration of them that radically redesigns them, depicting them as more of a hybrid between a humanoid and a worm. They then got a new model, as it is rather unlike GW's art department nowadays to create illustrations of creatures with no corresponding model. They are so derp.
He's got a hat. That means he's in charge.
|Forces of the Death Guard|
|Leaders:|| Chaos Lord - Daemon Prince - Sorcerer - Chaos Champion |
Malignant Plaguecaster - Plague Surgeon - Tallymen
|Troops:|| Biologus Putrifier - Blightlord Terminator - Chaos Spawn - Deathshroud |
Foul Blightspawn - Noxious Blightbringer - Plague Marines - Possessed
|Vehicles:||Chaos Land Raider - Helbrute - Plaguereaper - Predator - Rhino|
|Flyers:||Storm Eagle - Stormbird - Thunderhawk|
| Blight Drone - Defiler - Foetid Bloat-Drone |
Myphitic Blight-Hauler - Plague Hulk - Plagueburst Crawler
|Daemons:||Beast of Nurgle - Nurgling - Plaguebearer|
|Auxiliaries:||Cultists - Pestigors - Plague Zombie - Poxwalkers|
|Allies:||Chaos Daemons - Chaos Space Marines|
|Daemonic Forces of Chaos|
|Gods||Greater Daemons||Lesser Daemons||Daemonic Beasts||Daemonic Steeds||Cavalry of Chaos||Chariots of Chaos|
|Bloodthirster||Bloodletter|| Flesh Hound
|Juggernaut||Bloodcrushers|| Blood Throne |
|Great Unclean One|| Plaguebearer
| Beast of Nurgle
| Battle Fly
| Plague Drones
|Palanquin of Nurgle|
|Keeper of Secrets||Daemonette||Fiends of Slaanesh||Steeds of Slaanesh||Seekers of Slaanesh|| Hellflayer Chariots |
|Lord of Change|| Flamers of Tzeentch
Mutalith Vortex Beast
|Disc of Tzeentch||Burning Chariots|
|Daemon Prince||Fury|| Chaos Beast |