Extract Brain 
Sorcery
$0.29 #8493 0.39 5.1 years
Target opponent chooses X cards from their hand. Look at those cards. You may cast a spell from among them without paying its mana cost.
Click a line or tag to filter
Cards similar to Extract Brain 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.
Mindleech Mass76%
$0.40↑#73500.24↓20.9 years↑
"Whenever this creature deals combat damage to a player, you may look at that player's hand. If you do, you may cast a spell from among those cards without paying its mana cost."
Mindclaw Shaman76%
$0.29#11570↓0.08↓14.1 years↑
"When this creature enters, target opponent reveals their hand. You may cast an instant or sorcery spell from among those cards without paying its mana cost."
Villainous Wealth74%
$0.29#2406↑0.63↑11.9 years↑
"Target opponent exiles the top X cards of their library. You may cast any number of spells with mana value X or less from among them without paying their mana costs."
Silent-Blade Oni72%
$5.36↑#2844↑0.52↑14.3 years↑
"Whenever this creature deals combat damage to a player, look at that player's hand. You may cast a spell from among those cards without paying its mana cost."
Reversal of Fortune71%
$3.75↑#21041↓0.4522.3 years↑
"Target opponent reveals their hand. You may copy an instant or sorcery card in it. If you do, you may cast the copy without paying its mana cost."
Great Intelligence's Plan70%
$0.49↑#6682↑0.50↑2.9 years↓
"Draw three cards. Then target opponent faces a villainous choice — They discard three cards, or you may cast a spell from your hand without paying its mana cost."
Omniscience70%
$6.14↑#1022↑1.72↑14.1 years↑
"You may cast spells from your hand without paying their mana costs."