Do you mean put in Malygos? Also, kinda forgot about the Spellstone, what should I take out?

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Please remember to update now that Amalgam is dead

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The problem is that, most people (I) find that I have a hard time deciding what to sell. Everything is important. +1/+1 to 2 minions is worth around 2 gold (Menagerie bought+sold). Sylvanas’s Hero Power hence gives you 1 more gold the first time you sell a minion each turn. But sometimes, you focus on 1 minion. I agree with you that she should be Tier 3 for power, but frankly she is not very fun to play. And well, Hearthstone is a game, and it has a timer, so a lot of people (I) dislike playing her.