Tentacus
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Tentacus • Dis • Creature • Uncommon • Your opponent must pay you 1in order to use an artifact. • Artist: Caio Monteiro • Card Number: CotA:100, AoA:085, VM2023:087
Commentary
Tentacus's ability specifically uses the word Pay, and therefore Æmber used to fulfill Tentacus's cost is not considered to be lost to a steal effect.
Multiple copies of Tentacus require your opponent to pay one Æmber for each copy of Tentacus in your battleline before an artifact can be used. If they are unable to pay the full requirement, they pay nothing.
Source