Twisted Fate, The Card Master is a crazy strong mid lane champion with high burst after level nine when you max your Q, Wild Cards, and you get Lich Bane or Zhonya's. You have a low Cool Down stun, AOE slow, and mana regen ability in you W, Pick a card, empowered Basic Attacks with your E, Stacked Deck, and great roam potential that also helps pick off low health targets after team fights with your R, Destiny, and its second activation, Gate. Twisted Fate is fairly difficult to pick up because he requires quick decision making, but he has a very high skill ceiling, so there is a lot you can do with him.

High skill ceiling
Great during and after team fights
Low Cool Down Stun/Slow
High burst
Good Wave clear
Great Mana sustain
Easy pentas/penta steals ;)
Cool hat

Squishy
Hard to learn
Difficult to master
You are not Gross Gore
PAX Twisted Fate is not available via Hextech Chests