How much does Fireball cost

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A staple of Commander decks, Deadeye Navigator is one of the best ways to keep a high-value creature alive without needing a handful of counterspells
You put Twin on a key creature, you make infinite copies, and you swing for the win
Fact or Fiction was the big card draw card for such a long time before then people just assume it is good because it has had so much love over the course of magic history
If Valkyrie Aerial Unit costs around 4 mana or less, it looks incredible