15 cards where the lore includes “xantcha” or the name includes “sleeper” and the name includes “agent”

Yawgmoth's Edict (Urza's Saga #170)
Xantcha, Sleeper Agent (Commander Masters #362)
Xantcha (Vanguard Series #408)
Victimize (Commander 2014 #169)
Unnerve (Commander Anthology Volume II #81)
Sleeper Agent (Tenth Edition #178)
Priest of Gix (Duel Decks: Phyrexia vs. the Coalition #7)
Planar Void (Urza's Saga #149)
Oppression (Urza's Saga #143)
Ill-Gotten Gains (Conspiracy #114)
Healing Salve (Urza's Saga #16)
Darkest Hour (Urza's Saga #128)
Ajani, Sleeper Agent Emblem (Dominaria United Tokens #25)
Ajani, Sleeper Agent // Ajani, Sleeper Agent (Dominaria United Art Series #42)
Ajani, Sleeper Agent // Ajani, Sleeper Agent (Dominaria United Art Series #42)
Ajani, Sleeper Agent (Dominaria United #192)

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