Unlike the first game’s linear Scenario mode, *Tsu* centres on a tower-based main mode in which Arle Nadja selects opponents through a roulette system. Each floor has an experience-point requirement that must be met to progress. If all opponents on a floor are defeated before reaching that target, a final extra opponent appears. If the required total is still not reached after that battle, Arle is expelled from the tower, and the game ends.

Unlike the first game’s linear Scenario mode, *Tsu* centres on a tower-based main mode in which Arle Nadja selects opponents through a roulette system. Each floor has an experience-point requirement that must be met to progress. If all opponents on a floor are defeated before reaching that target, a final extra opponent appears. If the required total is still not reached after that battle, Arle is expelled from the tower, and the game ends.