Worms, for instance...easy made with greenstuff
I... might have to do this myself.... >_>
Now for the Warband name... Bloated Wolves! (maybe not )
Bloated Wolves would be cool, you could buy Space Wolves and convert them into nurgle dudes...
If not - what about Pox Spreaders, Fists of Decay, Infected Reach.... possibilities are endless!