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There are five Commander Brackets

Set: Ascended Heroes Rarity: Ultra Rare Collector Number: 267 Illustrator: DOM Pokmon 3rd Floor, 2 Central Plaza, Dame Street NE Suite 1600 Dublin, Irland, D02 T0X4

Your card choices are made based on what you intend to do during sideboarding, and what you do during sideboarding fits with your card choices

Leonardo, Cutting Edge: This ultra-cheap sneak creature pumps from lifegain

One with the Stars - 2.5 Slightly more expensive and complicated Blue removal enchantment

Ill certainly run it in Commander, and my combo-centric Cube is getting a copy (I doubt most Cubes will run it), but I doubt its strong enough for Legacy Storm