Invincibility training mode

I would like a training feature where you get to play without dying so that you get to really practice over and over again. Kind of like what Street Fighter games have where you practice your combos without killing the opponent so you keep throwing combos repeatedly. But the bot would play moves against you also not just stand still. And you can also play against people. And Flash would have one second cool down. The health bar can go down but you wouldn't die.