In case you didn't know, the Mr. Mime plus 2 Metal Energy / defender combo
doesn't work, according to the neo rules. With the handout given with the
Marril promo are a set of steps by which to attack. According to it, you
figure out damage effects of trainers( defender )and metal energy before
pokemon powers. For Example :

Scyther does slash to Mr. Mime with a defender.

Steps A - F

Step G - Apply defender damage ( 30 - 20 = 10 )

Step H - Apply pokemon powers ( Invisible Wall )

Steps I + J

Final Damage - 10

So, it is not a good idea to use any of these combos.

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