In the Eye of Chaos 
World Enchantment
$193.45 #21265 1.30 32.3 years
Whenever a player casts an instant spell, counter it unless that player pays 
, where X is its mana value.
, where X is its mana value.Click a line or tag to filter
Cards similar to In the Eye of Chaos 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.
Nether Void90%
$519.01↑#16171↑2.23↑32.3 years
"Whenever a player casts a spell, counter it unless that player pays 
."
."
Chancellor of the Annex86%
$2.86↓#10169↑0.80↓15.3 years↓
"Whenever an opponent casts a spell, counter it unless that player pays 
."
."
Ice Cave82%
$0.77↓#211260.92↓25.3 years↓
"Whenever a player casts a spell, any other player may pay that spell's mana cost. If a player does, counter the spell."
Cephalid Shrine80%
$0.29↓#30163↓0.44↓24.9 years↓
"Whenever a player casts a spell, counter that spell unless that player pays , where X is the number of cards in all graveyards with the same name as the spell."
, where X is the number of cards in all graveyards with the same name as the spell."
Chalice of the Void78%
$16.39↓#9268↑1.14↓22.9 years↓
"Whenever a player casts a spell with mana value equal to the number of charge counters on this artifact, counter that spell."
Planar Chaos74%
$2.31↓#7147↑1.41↑24.3 years↓
"Whenever a player casts a spell, that player flips a coin. If they lose the flip, counter that spell."
Counterbalance74%
$2.58↓#3290↑1.01↓20.1 years↓
"Whenever an opponent casts a spell, you may reveal the top card of your library. If you do, counter that spell if it has the same mana value as the revealed card."
Vexing Bauble70%
$2.17↓#1304↑0.51↓2.2 years↓
"Whenever a player casts a spell, if no mana was spent to cast it, counter that spell."
Lavinia, Azorius Renegade70%
$0.18↓#3183↑0.91↓7.6 years↓
"Whenever an opponent casts a spell, if no mana was spent to cast it, counter that spell."
Rethink70%
$0.10↓#230000.38↓26.3 years↓
"Counter target spell unless its controller pays , where X is its mana value."
, where X is its mana value."