Boreal Outrider 
Snow Creature — Elf Warrior
$0.24 #12952 0.20 5.6 years
Whenever you cast a creature spell, if 
of any of that spell's colors was spent to cast it, that creature enters with an additional +1/+1 counter on it. ( is mana from a snow source.)
of any of that spell's colors was spent to cast it, that creature enters with an additional +1/+1 counter on it. ( is mana from a snow source.)Click a line or tag to filter
Cards similar to Boreal Outrider 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.
Wildgrowth Archaic77%
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"Whenever you cast a creature spell, that creature enters with X additional +1/+1 counters on it, where X is the number of colors of mana spent to cast it."
Ultros, Obnoxious Octopus70%
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"Whenever you cast a noncreature spell, if at least eight mana was spent to cast it, put eight +1/+1 counters on this card."
Communal Brewing70%
$1.45↑#3516↑0.31↑2.1 years↓
"Whenever you cast a creature spell, that creature enters with X additional +1/+1 counters on it, where X is the number of ingredient counters on this enchantment."