Damn, this is a hard one. Forza is usually my go to choice for Xbox first party. I think I'll have to go with Killer Instinct. I'm surprised they haven't done much with the game since its launch with the Xbox One back in 2013. Hopefully they'll announce a new one during the Xbox Show. So yea, that's my choice. How about you, SW? What's your favorite Xbox first party game not including Halo,Gears, or Forza?