24 cards where the text includes “mutate” and the color identity ≤ BGU

Archipelagore (Ikoria: Lair of Behemoths #41)
Auspicious Starrix (Ikoria: Lair of Behemoths #144)
Boneyard Lurker (Ikoria: Lair of Behemoths #178)
Brokkos, Apex of Forever (Ikoria: Lair of Behemoths #179)
Cavern Whisperer (Ikoria: Lair of Behemoths #79)
Chittering Harvester (Ikoria: Lair of Behemoths #80)
Dirge Bat (Ikoria: Lair of Behemoths #84)
Dreamtail Heron (Ikoria: Lair of Behemoths #47)
Essence Symbiote (Ikoria: Lair of Behemoths #149)
Gemrazer (Ikoria: Lair of Behemoths #155)
Glowstone Recluse (Ikoria: Lair of Behemoths #156)
Insatiable Hemophage (Ikoria: Lair of Behemoths #93)
Migratory Greathorn (Ikoria: Lair of Behemoths #165)
Mindleecher (Commander 2020 #44)
Mysterious Egg (Ikoria: Lair of Behemoths #3)
Otrimi, the Ever-Playful (Commander 2020 #12)
Parcelbeast (Ikoria: Lair of Behemoths #199)
Pollywog Symbiote (Ikoria: Lair of Behemoths #63)
Pouncing Shoreshark (Ikoria: Lair of Behemoths #64)
Sawtusk Demolisher (Commander 2020 #64)
Sea-Dasher Octopus (Ikoria: Lair of Behemoths #66)
Souvenir Snatcher (Commander 2020 #38)
Trumpeting Gnarr (Ikoria: Lair of Behemoths #213)
Zagoth Mamba (Ikoria: Lair of Behemoths #106)

Their mind whirled with grand plans, never thinking of what might happen if they got to the end of the list.