Rogue. Key cards: Backstab, shiv, spell and weapon synergy cards. Rogues are the easiest class to 9-x with, they have tons of options to keep the board clear of enemy creatures and tons of wonderful synergies and bullshit. Coin + defias, dagger mastery + deadly poison, spell power + all the removal. For this reason they're also really common since a lot of people seem to know how imba this class is.
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