The 'Devil-Dog' is a variant of the Hellhound, switching the flamethrower for an oversized heat cannon. Armour caught in its rays swiftly liquefies, while the effects on soft targets is better left to the imagination.
The 'Banewolf' is another variant, instead carrying a chemical sprayer. Almost useless against buttoned-up AFV's, it is best used in soft-target rich environments where collateral damage is deemed acceptable.
Both turrets and body are compatible with Epic Scale Hellhound. No official rules for Epic: Armageddon, but good for alternate hellhound squadrons.