This is a "Scaling" Power which you can get into play easily with a card like Prepared or Acrobatics. Having enough Scaling to outpace the bosses, without having so much that you fall behind in the faster fights, is a key balance to strike to win at Slay the Spire.
This card is mainly about the thorns. Many enemies in STS2 multiattack, making this an excellent source of passive damage when combined with a defense-heavy deck. Being able to play a power via Sly is very effective as well.
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