28 cards where the illustration contains “prison”

Ashnod's Intervention (The Brothers' War #85)
Backup Plan (Conspiracy #2)
Barl's Cage (The Dark #96)
Bloodmist Infiltrator (Ravnica Allegiance #65)
Convicted Killer // Branded Howler (Shadows over Innistrad #149)
Convicted Killer // Branded Howler (Shadows over Innistrad #149)
Decree of Pain (Scourge #64)
Essence Capture (Kamigawa: Neon Dynasty #52)
Eternity Snare (Born of the Gods #37)
Fascist Art Director (Unhinged #11)
GO TO JAIL (Unstable #8)
Hieromancer's Cage (Core Set 2019 #14)
Hold for Ransom (Streets of New Capenna #16)
Mindbreak Trap (Breaking News #12)
Oubliette (Double Masters #100)
Oubliette (Arabian Nights #31)
Palace Jailer (Conspiracy: Take the Crown #18)
Palace Jailer (Tales of Middle-earth Commander #174)
Persecute (Urza's Saga #146)
Seatower Imprisonment (Alchemy Horizons: Baldur's Gate #27)
Serra Bestiary (Fifth Edition #60)
Shackles (Invasion #37)
Sterling Keykeeper (Outlaws of Thunder Junction #32)
Tyrant's Choice (Conspiracy #30)
Uncaged Fury (Shadows over Innistrad #188)
Unchained Berserker (Core Set 2020 #164)
Visage Bandit (Outlaws of Thunder Junction #76)
Warden of the Beyond (Magic 2015 #42)
You Find Some Prisoners (Adventures in the Forgotten Realms #169)

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