Agate Instigator 

Creature — Lizard Rogue
$8.99 #1209 0.28 2.1 years
Offspring 
(You may pay an additional 
as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever another creature you control enters, this creature deals 1 damage to each opponent.
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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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