No... If you summon Mew, and you're right next to it you are able to double your attack percent and lower your damage percent by half. It also makes you faster.

I know because I did that a couple times when I was playing. I don't know what I pressed but I did it twice. I think it was A, B, and R, maybe? I don't know. I came across it accidentally.

That was for SSB, I'm not too sure if you're able to do that in SSBM, because I rarely summon a Mew in Melee.

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