Vassal monster

Vassal monster is a (yet another) monster Sub-type created by Mauxs. They, combined with the ability "Awaken", allow one to perform a Sovereign Summon. Beyond this, no information can be given at this time.

Trivia

 * "Vassal", in the way it is used here, refers to "a holder of land by feudal tenure on conditions of homage and allegiance". The connection being that (most) Vassal monsters are subservient to their lord, the lords being Sovereign Monsters.