The upgraded version is way too strong. Once the enemy has a few creatures out play Aftermath fallowed by Plague, and then just SoSa for the rest of the game.
If they have 4 creatures, they will die in 5 turns.
If you have creatures out, they will ensure you EM thanks to SoSa.
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Mono
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is already very strong, adding this would elevate them to god status. Your card may be viable, but in
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it is just too good. I highly suggest moving it to
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as
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and
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have always been good together. In addition, your card is somewhat similar to VooDoo Doll, so it would be a nice fit.