The most likely Black/Grey looking fish out there right now with bumps on its back would be the False Albie. It also sounds like Albies based on your description of the fight. The picture looks like someone drew it on an etch-a Sketch and doesn't look like anything I can think of.
I couldn't see the pic either, like everyone said because the thread is from 2 years ago. Which brings up the point, why was this thread dug up in the first place?