Infernal Denizen 

Creature — Demon
At the beginning of your upkeep, sacrifice two Swamps. If you can't, tap this creature, and an opponent may gain control of a creature you control of their choice for as long as this creature remains on the battlefield.
{T}: Gain control of target creature for as long as this creature remains on the battlefield.
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Cards that do something similar expected a card that isn't here?
Reports become test cases the matcher is graded against before an update ships. Delvefall isn't a chatbot guessing, it compares the printed rules text of every card with plain math, and examples like yours decide which differences should count.