Those cards are Brainstorm, Sol Ring, Kodama's Reach, the Signets, Fire // Ice, and Cultivate
His article includes the quote "it appears that the two, three and four-mana slots are where the majority of your spells should be." Frank is right, if what you're looking to do is optimize your curve and minimize variation in gameplay, which is precisely what competitive players want to do
If Stax is more competitive and Group Hug is more focused on fun, why play Group Slug at all
Exile-based interaction has quite a few advantages over removal spells that destroy their targets thanks to near-permanent removal and its ability to skirt indestructible
And those are a different element entirely
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