Hidden Horror 
Creature — Horror
$0.16 #29422 0.05 29.4 years
When this creature enters, sacrifice it unless you discard a creature card.
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Cards similar to Hidden Horror 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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