He's very fun...once or twice !
Then it's always the same to me (my opinion, don't hurt me ;) ) : Get a lot of HP, Maximum Effort and This Card is Fire. This will one-shot most villain in solo and you will, usually kill any villain pretty quickly (understand, before dying to threats).

I find that a bit boring but once in while, why not... ;) The real problem I have with him is in multiplayer !
And the more players, the worse it gets :

• It Ain't Over... will soften the impact of all those Acceleration Tokens you'll add but it still more weight for the others to deal will every turn.
• He deals a lot of damage but he can't do it every turn reliably. In 4 players, something will mess a bit with your plan/health/cards and you won't be able to heal, Maximum Effort / "Yoo-Hoo!" and Fire as often as you'd like. It means you will deal huge burst of damage but overall you'll perform like most strong heroes.
• Finally, and mainly, YOU CAN DIE ANY TURN ! Yes, it seems weird because that's his entire thing but there are more ways to truly die than you'd think at first glance ==> a Boost that deals you 1 damage before the villain damages you, any Boost/Encounter card that deal you (indirect or not) damage, Kraken-like abilities, things that cancel your identity text-box like the #@%*ing Tabula Rasa 16 included in your nemesis set.
  I mean...what the hell, your game plan is to literally do THIS (being at 1 HP to "die") again and again so, at one point, you will inevitably die to one of those effects if the game last too long (and it will in 3-4 players if not everybody is rushing the villain)
• Okay, I'm not finished ^^ It is frustrating for YOU and for YOUR FRIENDS when you don't see the end of the game and have to wait 30 minutes or you force them to reset it. And sometimes you will die, discard your It Ain't Over... and make them lose because you thought 9 Acceleration Tokens was manageable :p

Anyway, he's incredibly good, but for solo, otherwise, you might be very frustrated.
Target Acquired can counter most things that can truly kill you, so I wouldn't play him without it in multi if I were to play him again (it saved me multiple times) :)