(Why did I draw Dumbbell butt first? I dunno, I guess because I don’t draw ponies from that angle often.) He has his cutie mark, it’s hidden by his wing.
 
But anyway, more head canon stuff. I have it in my mind that ‘Bell had one or three adventures of his own before he and Dash even considered each other friends. So basically before they reconciled their fractured childhood. Anyway, during the last days of standard education in Cloudsdale, there was a flash point, and he and Rainbow Dash had a pretty brutal fight. By that I mean noses were broken and some pony lost teeth. Both were suspended from Flight School, missing their graduation. While Rainbow Dash was given a second chance to repeat her final term, Dumbbell, just recently turned 15, decided to leave. A legal adult by Equestrian standards no one could make him stay.
 
Wandering lead to a lot of odd jobs. Eventually he found himself on the coast because it reminded him of home. There he found a job on the privateer vessel the ‘Minesweeper’, where he meets Gusty, a hard-nosed first mate. She has an expert talent for generating wind power. She can push heavy objects with it and manipulate smaller objects, so it’s like she’s an air bender with her horn. With enough power she can give herself temporary flight.
 
Dumbbell runs into Gabriel several miles away from Equestria, more details on how later. But Dumbbell’s initial impression of the guy was that, he never thought he’d know a creature more pathetic than Fluttershy until he met Gabriel. Poor guy has an atrophied soul. The picture on the left shows him with his wings clipped.
 
 
The kind of griffin he is? Well his top half is a vulture. His bottom half is like a Puma but honestly I wasn’t trying to be specific about it. There is supposed to be a tuft of fur at the tip of his tail, but due to poor grooming it all fell off.