Def during his days in Team Rocket! Also I hate drawing shoes so much aahhh I really need to put time aside to focus on practising those.
Def was quite well known during his Team Rocket days and for all the wrong reasons. The present Def is very different from the Def back then. Though, he still has his stubborness and is still pretty bold and not afraid to run right in to chaos with guns blazing (or Arcanine blazing, in this case!)