23 cards where the card is tagged “turn-face-up-trigger”

Aphetto Runecaster (Scourge #28)
Aven Farseer (Scourge #3)
Bonethorn Valesk (Scourge #82)
Case of the Pilfered Proof (Murders at Karlov Manor #9)
Deathmist Raptor (Murders at Karlov Manor Commander #168)
Experiment Twelve (Murders at Karlov Manor Commander #37)
Fatal Mutation (Scourge #66)
Mastery of the Unseen (Murders at Karlov Manor Commander #74)
Panoptic Projektor (Murders at Karlov Manor Commander #44)
Perimeter Enforcer (Murders at Karlov Manor #31)
Pine Walker (Khans of Tarkir #143)
Printlifter Ooze (Murders at Karlov Manor Commander #40)
Projektor Inspector (Murders at Karlov Manor #68)
Pyrotechnic Performer (Murders at Karlov Manor #140)
Roalesk, Prime Specimen (Alchemy: Murders at Karlov Manor #26)
Salt Road Ambushers (Murders at Karlov Manor Commander #184)
Secret Plans (Khans of Tarkir #198y)
Sleuth Instructor (Alchemy: Murders at Karlov Manor #2)
Sumala Sentry (Murders at Karlov Manor #233)
Temur War Shaman (Murders at Karlov Manor Commander #187)
Trail of Mystery (Murders at Karlov Manor Commander #192)
True Identity (Murders at Karlov Manor Commander #16)
Unblinking Bleb (Future Sight #45)

It is the moment of discovery, the triumph of the mind, and the end of these results.