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Enchantment — Saga

(As this Saga enters and after your draw step, add a lore counter.) I — For each opponent, up to one target noncreature artifact they control becomes a 0/4 Wall artifact creature with defender for as long as you control this Saga. II — Create a 3/3 green Dinosaur creature token with trample. It gains haste until end of turn. III — Destroy all Walls. Exile this Saga, then return it to the battlefield transformed under your control.