Okay, this is just a really quick pitch for an idea to nerf MK. Remember when Kai was given melee vulnerability? He was the first hero to actually have a passive had a negative attribute to it. I think MK could have a passive called Warm Up Routine where he's Slow for the first turn in any dungeon, then after a turn has passed and he's done his work-out, he's ready to fight and becomes Fast again. This way an Undead team could have a chance at taking him down, and he wouldn't be able to sweep an entire raid team right off the bat.
I think another good change would be to swap his first and last abilities. But that's not really my idea, that's a thing I've heard from others on the forums.
One last idea I had is to nerf his boosted dodge chance to only work for melee attacks, since Black Diamond (who I like to see as MK's counterpart) only has increased dodge chance for ranged attacks.
Favorite hero: Indigo
Currently: Trying to get as many runes done as possible. Takes a lot of money, man!