The Alpha Monsters are kaiju created by Toho that appear in Monster Kid, Monster Kid: Master of Monsters and Return of Monster Kid. They are monster forms of Max Stewart, May Stewart, Derek Stewart, Wendy Stewart, Morgan Stewart and Ava Stewart.
Known Alpha Monsters
Max's Alpha Monsters
- Phadorah
- Pyrogon
- Spidavon
- Mega Dragonfly
- Cluster
- Chaomera
- Dreeza
- Geo-Mite
- Crimson Phoenix
- Electro King
- Shadorax
- Glidron
- Squidorah
- Malerashi
- Phibicada
- Titandorah
- Mondorah
- Mega Manta
- Shadow Monster
- Dinogator
- Silverhead
- King Turtle
- Devil Squid
- Storrah
- Gold King
- Venragon
- Dexagon
- Puffo
- Dark Bat
- Glowton
- Thorgon
- Chimera
- Super Starfish
- Lizard Fish
- Vorgon
- Catapod
- Salavak
- Zamoeba
- Silrax
- Glaragon
- Super Dragon
- Armor Avian
- Monster Moth
- Taclytra
- Aquadragon
- Ultra Swordfish
- Abystor
- Moltrodon
- Britalak
- Ivopod
- Atavore
- Scorra
- Titanulon
- Spore
- Behemoth
- Phibigon
- Monsadorah
- Sharkadon
- Gargandra
- Crydusa
- Stormapede
- Mega Anemone
- Mandrake
- Ice Bug
- Solarwing
- Eon
May's Alpha Monsters
Derek's Alpha Monsters
- Anarpede
- Gold Beetle
- Mega Silverfish