During DC FanDome this weekend, James Gunn unveiled an official lineup for The Suicide Squad, putting the actors together with their character names for the first time. Or, at least, most of them. In the case of Nathan Fillion‘s character, all fans were given was his name: T.D.K. And while there have been a number of guesses as to exactly what “T.D.K.” might stand for — and plenty of The Dark Knight jokes — we wanted to break down a little bit about the character most likely to be his comic book counterpart, based on his costume logo as well as some recent rumors that could tie into it.