I'd say we need flexible cards, like
- 2 mana choose one: deal 3 damage or heal for 6.
- 2 mana choose one: deal 2 damage too all enemy minions or give +1/+1 to all friendly minions.
- 3 mana choose one: destroy enemy minion or give +3/+3 and taunt to friendly minion.
This way, one deck could have many ways to play the match.
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