Ruff is a one-shot character who appeared in Issue 4 of Sonic the Comic. He is a Norfolk Terrier dog and a resident of the Emerald Hill Zone. In the story Day Of The Badniks, Ruff and his friend Stripes witness what they think is Sonic tearing a Star Post out of the ground. They flee the scene only to be ambushed by Badniks, which capture them and use them as organic batteries. Once installed, the Badniks rendezvous with Doctor Robotnik and a group of other Badniks just in time to witness Sonic and Tails' capture and subsequent victory. Ruff and the others are released from their Badnik shells when Sonic - who had somehow resisted Badnik programming - threatened Robotnik.
Ruff's Badnik Form
The Badnik that installed Ruff appeared to have been inspired by Cerberus, the three-headed dog that guarded the ancient Greek Underworld. It was canine and had three heads, and a yellow paintjob. The coils it used to capture Ruff emerged from its mouthes. They were somewhat tongue-like as well since one of the heads appeared to be 'licking' its chops with one of these coils.