While the three decks are carefully balanced against each other, they each focus on differing play styles - corresponding to their different combinations of two ink types from the six card colours in Lorcana - so some may be easier to handle or more satisfying if you prefer to play a certain way
Animus of Predation: wow, this sounds really great
Remove all damage counters from Kadabra
Even when the other modes arent needed, dropping six +1/+1 counters on our commander is never a bad thing, especially for just four mana
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Luckily, Mercenary Informer is a card that does exist, and it hits any Mercenary regardless of converted mana cost...including itself, but there's no need to waste activations on that (unlike Ghosthelm Courier, it doesn't tap)