Mewtwo's backair gives him a huge boost at the apex of his second jump. he got boosts with all his airs, but the Bair is his most important gimping move in that game.
Shadowball is sort of unreliable because of the zig zag movement. most characters can sweetspot the ledge and avoid it. will be the same with this one lol...
it's hard to describe... eh, it has to do with the melee DJC...
heck with it lol, it'd be better to see what I'm talking about
my last melee combo video, a gimp fest actually... (not available on mobile fyi)
http://www.youtube.com/watch?v=IXa1fX3LLVc&hl=en&guid=&client=mv-google&gl=US
Taj's last combo video (he is way stinking better than I am/was)
http://www.youtube.com/watch?v=capoDHrZJng&guid=&client=mv-google&gl=US&hl=en
if you watch these two vídeos, then use the demo mewtwo, you will immeadiatly notice how much smoother the melee version is atm. this one is a work in progress so yeah. downthrow melee style looks better, he is floatier, and his jump is actually higher.
Long road ahead lol