Its not a great loss to not have a coin, as most Pokemon fans, unless theyre very new to the game, will have a number of coins laying around (and not likely to be used in games for the most part!)
That seems to be of value in an aggressive deck
I would try and address that by ensuring that the copying cannot self-perpetuate that spells are less likely to white copy spells, and creatures less likely to white copy creatures, or that they are reactive or defensive
Your typical early game sequences will look something like: Play a Falkenrath Gorger or value-play Faithless Looting to pitch a Bloodghast
He fits nicely into artifact or +1/+1 counter decks, but only when your pool already supports him
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