Flamekin Herald 

Creature — Elemental Wizard
Commander spells you cast have cascade. (Whenever you cast a commander, exile cards from the top of your library until you exile a nonland card with lesser mana value. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
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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.
Obscuring Haze 81%
$4.56#1513
"If you control a commander, you may cast this spell without paying its mana cost."
Fierce Guardianship 81%
$55.03#80
"If you control a commander, you may cast this spell without paying its mana cost."
Deflecting Swat 81%
$65.28#77
"If you control a commander, you may cast this spell without paying its mana cost."
Flawless Maneuver 81%
$20.35#184
"If you control a commander, you may cast this spell without paying its mana cost."
Deadly Rollick 81%
$28.15#112
"If you control a commander, you may cast this spell without paying its mana cost."
Myth Unbound 81%
$3.16#9640
"Your commander costs {1} less to cast for each time it's been cast from the command zone this game."