Another common way of playing with fewer people, like 3-4 players, is to draft one card and burn another (as in, removed the card from the card pool put the matches away!)
But this isn't all downside
I have opted for aggression whenever presented with a choice between comparable effects, choosing Lone Missionary over Arashin Cleric, Lyev Skyknight over Reflector Mage, etc
This is also why three-drops are a bit limiting in blue decks: it is just too hard to slot in a later cantrip and play a three-drop after
You could always play Black Lotus, but for a long time Time Vault wasn't just restricted
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