As a note this is mostly just thoerycrafting right now due to the fact the meta for black Carnival hasn't been developed yet.
Black Carnival is a toolbox deck based around Valor SIGNI that wants a massive amount of cards in the trash for effects, some of her cards are based around gaining power as well.
As with most post incited LRIGs the choices for Carnival's lower levels is based around the number of coins you want. In key format Carnival cannot generate a coin when she grows to level two, so she currently caps out at five coins in key format. however in All-star she can have six coins. Of course you can only have five coins at a time, so if you wish to gain the maximum amount of coins use some of them for an effect or a key.
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