The Octomammoth was once an ordinary octopus that was mutated by unspecified "underwater experiments." Tellah comments that it is "an octomammoth," indicating it is not the only mutation of its type. Though no others appear in the game or its sequel, Final Fantasy IV: The After Years, two similar monsters appear, Octo-Kraken and Cooler Mammoth. Palom mentions that the Cooler Mammoth once gave Tellah trouble, indicating it may be the same creature.