Magna Braban: Henreki no Yuusha is a Japanese-style RPG with party-based combat and random enemy encounters. The game's main view is an overhead map of a specific location, such as a town, where the characters move and can interact with NPCs. Upon leaving an area, the view changes to a larger overworld map showing locations of interest. The battles are viewed from an isometric perspective and the characters automatically engage and perform their actions. While the player does not directly control any of the characters, they can pause the battle at time and assign new strategies (such as melee, use long-ranged attacks or use Magic) to each character. Experience points and gold are awarded after each battle, the later of which can be used to purchase equipment and items.

The Demon King and his monster armies have been attacking the human kingdoms in an effort to exterminate them all. One day a young boy named Alex is attacked by four monsters but is saved by a Knight of Anatea. Alex, the son of a shepard, grows up idolizing this knight and once the proper age, wishes to enroll in the Arena tournament, though his family forbids him. Entering the tournament Alex and two other warriors: Gina the Magician and Getz the Mercenary, all are defeated in the first round and sent to the Inn to recuperate. However during their absence, the Demon King plans a surprise attack on the Arena and kills everyone there. As the only surviving warriors from the tournament, Alex, Gina and Getz are mistakingly assumed to be strong enough to withstand monsters, and made knights by the King and given the mission of defeating the Demon King. They set out on an epic journey...