Enough about the Charizard-tail thing.
Also, Pyroroth, you're ruining this topic with fanboyism and bad jokes "pewpewpew"? Are you just trying to up your post count? Also, watch out for double posts.
Onto the topic. I really can't see Ivysaur firing the cracker launcher. It can't fit in his mouth AND face the right way, plus he has pretty much no way of pulling the trigger like that. His vines holding it seems plausible, but he has no fingers to grip with. Maybe wrapping them around it... That could work. As long as it doesn't look awkward with him holding it a foot away from him. Maybe holding it close over his back.
As for Charizard running, there's gotta be a better way than fake-gliding. But I can't think of one.
And taunts for ivysaur are ridiculously easy.
/\ Looks at the screen, grins, saying "Iiiivee-SOAR", moving his head a little as he does so.
< > Rears up on his hind legs, vines out pointing up above him, as in the crappy illustration below, but facing sideways
\/ Shakes his green backside similar to what Venuaur did in Melee, but without the earthquake.
`: