I think my biggest problem with alchemy is the potions in general. I like the idea of them but unless you have a few Alchemy cards, it's almost not worth it to have them in there. I like playing pure randoms, so it's almost either exclude Alchemy, or use at least half Alchemy, so I'd rather just use no Alchemy. I also think Philosopher's Stone and, of course Possession are the most annoying cards in the game, though I suppose Philosopher's Stone probably isn't so bad online.
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