cheapest mtg set booster box Magic: The Gathering Zendikar Rising | 30 Packs (360 Cards) + 1 Box Topper traditional foils Magic: The Gathering Trading Card

Math Time Disclaimer: Any of the below writing and statement of the problem is the result of my requesting that some friends help me out

The crucial thing to remember about the spell-cheating element of Buster Swords trigger is the mana value limit is dictated by combat damage dealt to a player, not their creatures

As such, if Vivi has the power for it, it's better to use Vivi's effect for mana rather than from lands or mana rocks to cast spells on your turn

Namely, the legendary Pocahontas Peacekeeper card, which has a fun shift-related ability

There's also Magistrates Scepter , a 3-cost artifact that can be powered up with charge counters then used to take an entire extra turn