Seems the Rat King went through some cosmetic changes between when I used to watch the Ninja Turtles cartoon and the 2011 comic series. This one also seems a lot more competent and menacing than what I remember. And he'll be making his way to your tabletops in the Heroes in a Half Shell set for HeroClix.
The Rat King sure is a sneaky fellow. He's able to jump between various bits of hindering terrain using a free action. He also has phasing/teleport on his dial, for even more "I wanna be over here"-ness. He also has the ability to use Stealth and Mind Control as if he had... a whole bunch of special abilities I'm not 100% sure what they are (I can only memorize so many game systems special rules, after all). Lots of things to mess up your opponent's plans, for sure.