And then theres the power creep
First, all the strengths of Chainer, Nightmare Adept apply here
Creatures aren't the only card types to utilize the Morph mechanic

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While you might not imagine a Stadium card would ever find itself among the most valuable cards in a set, the Double Crisis chase cards do much of the heavy price lifting
Other times its a strategy - for example, knowing you want to play as many lands as possible or win using an alternate win method, such as milling your opponent so that they lose when they cant draw any cards