Artifact spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting an artifact spell pays for 1 or one mana of that creature's color.)
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Burgeoning143 · rare$33.71
Atraxa, Praetors' Voice28 · mythic$33.28
Tymna the Weaver48 · rare$29.75
Thrasios, Triton Hero46 · rare$26.85
Lurking Predators156 · rare$19.52
Homeward Path301 · rare$19.37
Reyhan, Last of the Abzan40 · rare$17.76
Chain of Vapor84 · uncommon$15.57
Benefactor's Draught21 · rare$14.53
Swan Song98 · rare$14.07
Yidris, Maelstrom Wielder50 · mythic$11.71
Breath of Fury121 · rare$11.68
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