Shockwave is a range move, and fast to use. It's possible for him to get it out quickly. And Roo is really quick now with the God Hand, he can slip into enemy lines in right after the match begins. Roo is already pretty durable, he can tank machinegun fire and stuff, and with the God Hand that's amplified.
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You beat yourself up with your past. Don't blame yourself, blame the world. Blame God. Blame me.