tech chasing is the act of following your opponent after a knockdown. There are three options of techs, left roll, right roll, and neutral. Tech chasing is the act of punishing either of the three options with an attack

Mewtwo is a poorly designed character, having almost no kill moves and no neutral game. Mewtwo only has a few redeeming qualities, such as his amazing recovery and powerful grabs. It is very hard to combo with/against Mewtwo because of his lack of speed and floatiness.