A commander that gives all your spells delve
That may not seem like much but if the opponent is unable to take Calhoun out in one strike, that resist +1 may effectively double her health
Blinking a creature essentially resets it to how it enters the battlefield, so even creatures that were attacking when they were blinked enter untapped, out of combat, and with summoning sickness
Other Builds What else can you do with Mogis, God of Slaughter if you dont want to blow up the world
Loads ranked cards from Mystery Booster: Convention Edition Exclusives
There's also the tiny problem of this costing seven mana, all of it colored, but the combination of both winning the long game and keeping you alive to see it makes seven feel cheap, and there's enough behind this card that there is no need to worry about following it up with another copy unless your opponent can fire one back at you