Ghosthelm Courier 

Creature — Human Wizard
You may choose not to untap this creature during your untap step.
{2}{U}, {T}: Target Wizard creature gets +2/+2 and has shroud for as long as this creature remains tapped. (It can't be the target of spells or abilities.)
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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.
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