Aetherstorm Roc 
Creature — Bird
$0.25 #8074 0.33 9.9 years
Flying
Whenever this creature or another creature you control enters, you get 
(an energy counter).
(an energy counter).Whenever this creature attacks, you may pay . If you do, put a +1/+1 counter on it and tap up to one target creature defending player controls.
. If you do, put a +1/+1 counter on it and tap up to one target creature defending player controls.Click a line or tag to filter
Cards similar to Aetherstorm Roc 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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"Whenever this creature attacks, you may pay . If you do, put a +1/+1 counter on it."
. If you do, put a +1/+1 counter on it."+1 more matching line
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. If you do, put a +1/+1 counter on it."+1 more matching line
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"Whenever this creature attacks, you may pay . If you do, put a +1/+1 counter on it."
. If you do, put a +1/+1 counter on it."+1 more matching line
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"Whenever this creature attacks, you may pay . If you do, put a +1/+1 counter on it."
. If you do, put a +1/+1 counter on it."+1 more matching line
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"Whenever this creature attacks, you may pay . If you do, put a +1/+1 counter on it."
. If you do, put a +1/+1 counter on it."+1 more matching line
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"Whenever this creature attacks, you may pay . If you do, put a +1/+1 counter on it."
. If you do, put a +1/+1 counter on it."+1 more matching line
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"Whenever this creature attacks, you may pay . If you do, put a +1/+1 counter on it."
. If you do, put a +1/+1 counter on it."+1 more matching line
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"When this creature enters, you get ."
."+1 more matching line
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"When this creature enters, you get ."
."+1 more matching line
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"When this creature enters, you get ."
."+1 more matching line
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"When this creature enters, you get ."
."
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"When this creature enters, you get ."
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"When this creature enters, you get ."
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"When this creature enters, you get ."
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"When this creature enters, you get ."
."
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"When this creature enters, you get ."
."+1 more matching line
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"When this creature enters, you get ."
."
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"Whenever a land you control enters, you get ."
."