Gamers navigate an open world to help a young prince reclaim his homeland and avenge the murders of his fiancée and the king in Final Fantasy XV. The game is set on the planet Eos and stars Prince Noctis of Lucis, a magic-based society flanked by four technologically advanced nations. The powerful nation of Nilfheim has been warring with Lucis over a magical crystal, but a peace deal is brokered, and it includes a unifying wedding of Prince Noctis and Lady Lunafreya of Tenebrae. But Nilfheim attacks when the prince is away, and he and his companions must fight back to save Lucis.

The characters and locations in Final Fantasy XV are designed to be more modern and realistic than in most games in the series, though players will confront a variety of fantasy creatures as they freely explore the countryside. The game uses the real-time Active Cross Battle system, which maps traditional RPG menu commands to specific buttons, and gamers can issue orders to other party members or team up for combo attacks. Noctis can switch between four primary weapons, including swords, lances, shields, and guns, and players can also use two types of magic, and call large monsters into battle.

The large game world can be traversed on foot, on bird-like chocobos, or in the car/airship Regalia, and gamers can place markers around the map to help them navigate. Dynamic weather and day/night cycles affect the use of magic and the appearance of certain monsters, and if characters don't set up camps and sleep at night their combat abilities suffer. Any experience points earned during battle get converted into new levels when characters sleep, and gamers can also cook or fish at campsites. When not in the wilderness, players can head into cities to rest, buy equipment and cooking ingredients, and take on side quests.

This Day One edition comes with the full game as well as the legendary Masamune in-game sword.