11 cards where the text includes “backup” and the colors < BR

Archpriest of Shadows (March of the Machine #89)
Consuming Aetherborn (March of the Machine #97)
Cragsmasher Yeti (March of the Machine #333)
Death-Greeter's Champion (March of the Machine Commander #30)
Fearless Skald (March of the Machine #138)
Gloomfang Mauler (March of the Machine #108)
Hangar Scrounger (March of the Machine #142)
Mirror-Style Master (March of the Machine Commander #32)
Redcap Heelslasher (March of the Machine #161)
Scorn-Blade Berserker (March of the Machine #124)
Voldaren Thrillseeker (March of the Machine #171)

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