Drury Walker, ex-convict - a muscle jobber put away after a gig got raided by Batman. ‘Reformed’ and hired after release by a corrupt Gotham businessman as security detail. Businessman ultimately exposed by Batman too, though nothing able to incriminate Walker. Press ran stories bringing up Walker’s time spent and making allegations that he must have been in on it or even ringleading it, but without evidence Walker was successfully able to bring libel suits against them and score payouts settled out of court before disappearing, presumably ‘retiring’ with his money.
What he was actually doing was turning himself into a Batman For Criminals, using his background and skills as muscle-for-hire and protective detail to market himself as premium heavy for tough jobs. He gets hired on a couple watch-jobs and then lands a small gig as top muscle on a heist for a mid-level mob boss hoping the planned score will put him on a Falcone/Maroni playing field.
Can either have:
job going well even with an appearance from [batfam member], but mockery over his chosen attire and tools and crafted persona causing Walker to snap, subdue the jobbers he was on the heist with, and take the score entirely for himself
OR
have the job go okay until the appearance of [batfam member], where Walker is somehow the only guy left standing and manages to escape with the heist’s score while realizing he’s still outclassed.
Either way Walker’s now sitting on the score plus cash plus the new enmity of the mob boss who hired him plus the batfam are now aware of him, and realizes he’ll be blacklisted from Gotham’s criminal underworld - so it’s time to start building his own crew and organization and creating the jobs, not just getting hired for them.