Bone Picker 

Creature — Bird
This spell costs {3} less to cast if a creature died this turn.
Flying, deathtouch
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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.
Grim Reaper's Sprint 100%
$1.59#4498
"This spell costs {3} less to cast if a creature died this turn."
Macabre Reconstruction 83%
$0.10#14990
"This spell costs {2} less to cast if a creature card was put into your graveyard from anywhere this turn."
Death-Rattle Oni 80%
$0.16#17187
"This spell costs {2} less to cast for each creature that died this turn."