Axiom of Maria is an action-adventure game set in Seoul, which has become a ghost town. Kay, a former instructor of the 707 Special Missions Group, stands against the 15th AI Squadron (AISOC) to protect her family.

Swordplay Action
Axiom of Maria pursues fast, intense, and easy action. Enemies primarily use guns, and the protagonist Kay wields a reactive sword that responds to enemy fire.

Motorbike Action
While Kay is on her motorbike, it moves automatically. The player controls Kay to approach and attack enemies or to leap over elevated roads.

Story
Due to population decline and epidemic, Seoul has become a ghost town, and the preservation and management of the city is entrusted to AI. The deceased are backed up into a virtual world called Beyond. Death has come to be called migration.

The group called Irregulars aims to liberate the dead by destroying Beyond. The 15th AI Squadron (AISOC), which manages Beyond, seeks to eliminate the Irregulars.

Kay, a former instructor of the 707 Special Missions Group, is detained by the AISOC with her daughter when her husband is revealed to be an Irregular and disappears without a trace.

A group called “the School” rescues Kay and her daughter from the AISOC. The School, led by the Principal and a person called Teacher Jeong, starts assisting Kay in finding her husband.