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Concerted effort and a bunch of creatures to proc it.
Get Concerted Effort out ASAP. The creatures have a variety of abilities to combo with it, especially double-strike and protection. The side-board helps you sub the correct protections in to deal with the colors the other player is using. It may be worth subbing in some Vexing Shushers for use against blue as well as or instead of Guma, as hosing counter-spells might be of more value than pro-blue. Revoke existence is to sub in if you are having trouble with artifacts or enchantments, obviously.
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