This plus adrenaline would be way OP - returning 4 cards a round to your deck.
I'm sure Zanz would do what he did to pufferfish/scorpions/devourers, if a card like this was ever implemented.
More dangerous is Fractal, which currently cannot be reduced. Therefore, My idea would be to make its health 4-N, so at most you can have 3 on the field (like a reverse scarab).
This card would be very interesting if you could somehow get it on your opponent's field (and thenpossibly quint it). Much less consuming than an Eternity. However, the only way I think it could be done is by using nightmare, and even then there are no guarantees the opponent will even have the quanta to play it. (Mindgate would also give the opponent this card, but you cannot force a mindgate upon your opponent)
(I guess if you PVP2'd it, since everyone seems to be playing speedbows, and aren't always super intelligent that strategy could work
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