アーサーの伝説-Excalibur- is a free-to-play role-playing game developed by X-Legend Entertainment Co. Ltd. for Android devices. The game is set in a dark era where the world is in chaos due to the struggle for the "Holy Grail's blood" by the "Child of God" and the "Calamity." The players' role is to lead a group of knights and explore various regions to create their own unique hero legend.

The game offers a high degree of customization, allowing players to create their own unique characters with a wide variety of costumes and accessories. The battle system is based on a classic job system with an emphasis on impactful skills. Players can choose to become a magic swordsman who manipulates elements or a magic fighter who excels at both martial arts and magic. The game also features a large continent to explore, where players can engage in mini-games such as fishing, collection, alchemy, and forging to enhance their characters. The game also offers a variety of social features, including a marriage system, to make sure that players never feel lonely on their adventure.