New characters

Why is it every time a new character is introduced, that toon is basically Invincible?
It's crap!
Every time there is a new addition there is always some player who pays to get him/her to top level, and then it's next to impossible to beat them. Then there are the endless posts and discussions until the dev team gets tired and nerfs them. How about for once put out a player that is in a competitive level, and stop the endless drama.
And try to remember that all sorts of people play this game not just visa platinum card holders.