Elephantidae Mimicry – The ability to take on the form and/or characteristics of an Elephantidae. The Elephantidae family includes elephants and mammoths.
Mammomax (Marvel) first appears in X-Men V2 #161.
Inexplicably there was only one issue of the Power Pachyderms (Marvel).
Loxo – TSR 2145 Monstrous Compendium Annual Volume 1
Mammoth – D&D 4th Edition – Monster Manual 2
Slon Gravekeepers – Creature Collection III. Savage Bestiary
Slon – Creature Collection III. Savage Bestiary
Tundra Lords – Creature Collection II. Dark Menagerie
Yag-Kosha – Annual Conan the Barbarian #1
Fire Tusk is a high tech sort of elephant!