Board Thread:Super Smash Bros. Discussion/@comment-25462958-20140925145732/@comment-6604133-20141005210239

GreninjaBoss11 wrote: Guys just so you know, Mewtwo will be playable. I can give three good reasons: Fan Demand, Fan Demand, Fan Demand, Why not? (BTW I am aware that I made four reasons.)

Because he's already a collectible trophy. That's why not.