The Legend of Legacy is a turn-based role-playing video game for the Nintendo 3DS handheld video game console, developed by Cattle Call. The game was first published for Japan by FuRyu in January 2015, then localized by Atlus USA to be published by Atlus USA for North America in October and by NIS America for Europe and Australia in February 2016. A remaster was released in 2024 for the Nintendo Switch, PlayStation 4, PlayStation 5, and Windows. The story takes place on the legendary lost continent of Avalon, where eight adventurers explore and fight to uncover its mysteries.

The production of The Legend of Legacy began in 2013; multiple industry and genre veterans were joined the development staff, including director Masataka Matsuura, designer Kyoji Koizumi, promotional artist Tomomi Kobayashi, writer Masato Kato, and composer Masashi Hamauzu. The game was chosen for localization by Atlus USA due to its positive impression on staff and their previous relationship with FuRyu. Upon release, the game received mixed reviews. The core developers used ideas from the concept stages of The Legend of Legacy to develop The Alliance Alive.

The Legend of Legacy is a role-playing video game in which players take control of seven different characters as they explore the island of Avalon; each character has different starting statistics (stats). While each scenario starts out with three pre-set characters, the rest of the cast can be recruited, but will only gain stat increases if they are in the party. The chosen protagonist operates from the town of Initium on Avalon, exploring areas of Avalon after being provided with a blank map. Walking around areas automatically generates a map, displayed on the bottom screen of the Nintendo 3DS. During exploration, the party can also explore dungeons, and find chest both above ground and in dungeons containing items and currency. Once each region is explored, the mission turned in for currency and replaced with a new blank map and new area to explore. It also enables monster numbers to be reduced, and aids in dungeon exploration. Completing maps or buying them within Initium progresses the game's narrative. The player can save both at specific locations and create a quick save at any point during the campaign.

Initium acts as a hub for the party, where they can buy and sell equipment and maps, and talk with non-playable characters to learn story and gameplay information. The player can use ships to trade from Initium in a mechanic tied to the 3DS' StreetPass functionality. Players send out ships with cargo to trade with other cities, bringing currency and items. Larger ship types take longer to return from trips, but have a higher chance of bringing rare items. Using StreetPass allows players to fill ships sooner and see them return earlier. Completing the game allows players access to a New Game Plus option, carrying over character statistics and money, while making advanced weapons available for purchase from the start.

During exploration, enemies appear as sprites within the environment, which can be avoided or engaged and will pursue if they see the party. Battles use a turn-based battle system within a themed arena, with both player and enemy parties being arranged on a grid in arrangements called "Formations". Each formation has a selection of "Stances", which are divided into attack, defense and "support" abilities such as healing. Player formations are created between battles, with the party able to change formation once during their turn. The party has access to eight weapon types, which can be freely assigned to each character and impact their statistics and battle abilities; Fists (melee combat) Long and Short swords, Axes, Spears, Staves, Bows and Shields. Each party member can partner with Elemental spirits aligned to Fire, Air, Water and Shadow once they find special relics during exploration. Once a partnership is established, the party member can use "Charms", powerful magical spells unique to each element which can unleash powerful attacks or protect the party from taking damage. Charms grow stronger the more they are used. Winning a battle rewards the party with statistic increases, currency and items.

Contrary to the majority of role-playing games, character stat increases do not rely on an experience point system, instead depending on usage during battle. Winning a battle awards the party with items and currency, but also randomized stat increases, raising a character's health or attack power. Each weapon has specific abilities dubbed "Arts"; using an Art often enough results in it either upgrading to a more powerful form or the party member learning a new skill for that weapon in a process dubbed "Awakening". Charms also grow stronger the more they are used, and characters grown more proficient in their Formation roles the more they are used in a particular formation.

The Legend of Legacy takes place entirely on the island of Avalon, which was discovered ten years before the game's opening and identified with a legendary lost continent whose inhabitants walked alongside gods; the island, while now mostly wild and dominated by monsters, housed ruins crafted with the assistance of natural spirits dubbed "Elementals", and ancient stones which detail the island's past when activated. A legendary artifact of Avalon is the Star Graal, which is said to grant "eternity" to its bearer, and prompts dozens of adventurers to travel Avalon in search of it. The only active town on Avalon is Initium, founded by the King of Adventurers, a man who discovered the island ten years before.

Each of the seven playable characters come to Avalon with different objectives. Meurs is the last Elementalist, a person with the power to communicate with Elementals. Bianca is an amnesiac who wakes up on Avalon only remembering her name. Liber is lured to Avalon with the promise of adventure and treasure. Garnet is a Templar in service to the Holy Order. Eloise is a seductive alchemist pursuing the secret of eternal life. Owen is a legendary mercenary who will take any job if the price is right. Filmia, the only native of Avalon, is a frog prince from a lost kingdom. Each of the seven protagonists are drawn to Avalon for different reasons: Meurs is summoned by the distressed calls of Elementals; Bianca goes on a quest to discover her identity, Liber is in search of the Star Graal as treasure; Eloise searches for the Star Graal to discover the secret of immortality; both Garnet and Owen are sent by the Holy Order to investigate Avalon due to its rumors of living gods and their consequent heretical status; and Filmia resolves to rebuild his kingdom.