Mastadooms are large skeletal mammoths encountered on Star Hill in Super Mario RPG: Legend of the Seven Stars. Mastadooms are possibly the most powerful enemy on Star Hill having an arsenal of physical attacks and the powerful "Drain Beam" attack which hurts all party members. A Mastadoom's regular attack consists of hitting its opponents with its long trunk. Mastadooms are strong against Thunder, but their main weakness is Fire.
Like most powerful enemies in Super Mario RPG: Legend of the Seven Stars (Reachers, Hippopos, etc.) only one Mastadoom ever appears in battle. There is also an unused enemy named Mastablasta, which is a blue colored version of Mastadoom. They could actually summon Goombas to help them in battle, and had the psychopath, "Life is tough, ain't it?"
 Names in Other Languages
- Mastadooms are likely based on the real life extinct animal, the mastodon.