The Soul Stone {1}{B}

Legendary Artifact — Infinity Stone

Indestructible

{T}: Add {B}.

{6}{B}, {T}, Exile a creature you control: Harness The Soul Stone. (Once harnessed, its ∞ ability is active.)

∞ — At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.

Prints	USD	EUR	TIX
Marvel's Spider-Man Promos	✶ $135.95
Marvel's Spider-Man #66	$54.90	€40.22
Marvel's Spider-Man #242	✶ $32,999.99
Marvel's Spider-Man #243	✶ $1,278.80
Through the Omenpaths			4.74
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"Harnessed" is a designation that the permanent has once an ability instructs you to harness it. It has no special rules meaning other than being a designation that the ∞ ability (and, theoretically, other effects) can see. (2025-09-19)
Until it is harnessed, The Soul Stone doesn't have the ability listed after the infinity symbol. It also doesn't have that ability in zones other than the battlefield. (2025-09-19)

Being harnessed isn't copiable. If something else becomes a copy of The Soul Stone, it must be harnessed separately. Similarly, if The Soul Stone is already harnessed and becomes a copy of something else, it stays harnessed, though it's very likely that won't be relevant until that copy effect ends. (2025-09-19)