Gamers control a team of psychically gifted warriors as they attempt to save the world from destruction in Lost Dimension. A mysterious, destructive tower known as the Pillar has appeared in the world, and with it comes a man named The End, who wants to bring about the apocalypse. Gamers fight back with Sho Kasugai, an 18 year old with the gift of precognition, and a handful of psychic fighters from the S.E.A.L.E.D. team. The action unfolds in a tactical, turn-based manner, with players meeting in the lobby of the Pillar to prepare before heading up to higher floors for battle.
Each of the characters possesses a unique Gift, such as Sho's ability to see the future, Yoko's telepathy, Agito's teleportation, or Sojiro's healing powers, and as they make their way through battles fighters earn experience that can be used to upgrade their Gifts. Characters move freely in the battlefield (within their movement range), and they can pass their turn to a teammate, team up for assist attacks, or unleash berserk attacks that target friend and foe alike.
Lost Dimension also features a branching narrative, with the choices a player makes having an effect on the game's ultimate outcome and on the fate of the other characters. The End has placed a traitor within the ranks of S.E.A.L.E.D., so gamers must form trusting relationships while in the Lobby and use Sho's ability to see the future to find the mole. In addition, team members must vote for one character to be erased upon completion of each floor of the Pillar. Characters have their own suspicions, but Sho can influence their votes.