That's because exiling the card happens as part of paying the activation cost, not as part of the effect
(Each deals damage equal to its power to the other.) At the beginning of each upkeep, if a player cast two or more spells last turn, transform this creature
Creatures (7) Lands (18) Spells (35) 4 Sleight of Hand 4 Serum Visions 1 Peer Through Depths 4 Gifts Ungiven 4 Desperate Ritual 4 Remand 3 Grapeshot 4 Manamorphose 4 Pyretic Ritual 1 Apostle's Blessing 2 Past in Flames Sideboard Creatures (6) Lands (17) Spells (37) 4 Sleight of Hand 4 Serum Visions 4 Gifts Ungiven 4 Desperate Ritual 4 Opt 3 Remand 3 Grapeshot 4 Manamorphose 4 Pyretic Ritual 1 Noxious Revival 2 Past in Flames Sideboard Now, storm is a mechanic that I despise, but if we just banned Grapeshot or Past in Flames, Im confident that another win condition would take up the mantle
All told, the general strategy is pretty straightforward: ramp up a variety of mana, fill your board with warriors, keep attacking to generate more warriors, and eventually trigger the ability mid-combat
We think the new art card will be of the Raya from the front and center of the trove/booster box like with Mickey Mouse Brave Little Tailor from the first set