Double targeting is currently not allowed.
Well, there you go.
Thematically, I would suggest this:
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: Target a creature. Rob it of one attack or one defense.
The ATK/DEF would be chosen by which is higher on the targeted creature. You gain one of that stat.
I would also suggest that you lower the attack to 0 | 1 starting out, but keep the defense level. This makes it more balanced.
If anyone argues OP, either raise the ability cost to
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or lower the defense by one.
AFTERTHOUGHT:
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for the ability: can you show your reasoning/arguments?
Nice avatar as well.