Goblin Maskmaker 
Creature — Goblin Citizen
$0.04 #21472 0.25 2.6 years
Whenever this creature attacks, face-down spells you cast this turn cost 
less to cast.
less to cast.Click a line or tag to filter
Cards similar to Goblin Maskmaker 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.
Dream Chisel90%
$3.84↑#13566↑0.14↓23.9 years↑
"Face-down creature spells you cast cost less to cast."
less to cast."
Obscuring Aether87%
$0.17↑#11132↑0.12↓11.4 years↑
"Face-down creature spells you cast cost less to cast."
less to cast."
Hardened Berserker86%
$0.03↓#240460.06↓11.4 years↑
"Whenever this creature attacks, the next spell you cast this turn costs less to cast."
less to cast."
Kadena, Slinking Sorcerer86%
$0.39↑#12052↑0.41↑7.0 years↑
"The first face-down creature spell you cast each turn costs 
less to cast."
less to cast."
Panoptic Projektor84%
$0.30↑#9031↑0.62↑2.6 years
"
: The next face-down creature spell you cast this turn costs less to cast."
: The next face-down creature spell you cast this turn costs less to cast."
Cheering Fanatic78%
$0.14↑#198780.36↑8.2 years↑
"Whenever this creature attacks, choose a card name. Spells with the chosen name cost less to cast this turn."
less to cast this turn."
Valakut Fireboar70%
$0.19↑#27487↓0.2516.4 years↑
"Whenever this creature attacks, switch its power and toughness until end of turn."
Stone Calendar70%
$14.67↑#202700.48↑32.1 years↑
"Spells you cast cost less to cast."
less to cast."