Delving into the Labyrinth and exploring the First Stratum, Tutelary Forest, the player meets Lili, a female Celestrian necromancer with pink hair and pale blue skin.

Together, the player's party and the duo encounter the Undead King, a monstrous being that was formerly Lili's partner, Crow, until he stole the Ring of Undying.

Proceeding into the Fourth Stratum, a series of crystalline caves called the Lucent Hollows, the player's party begins to spot a mysterious girl wearing a brown cloak, with pale hair and grey skin.

There, the strange girl reveals herself as Arken, saying that she created the entire labyrinth to contain the Eternal Tyrant, an ancient, evil being that once held complete control of a desolate Arcania.

She then decides to leave the planet, her task fulfilled, but asks the player to escort her to the next one she is to watch over, unlocking a post-game dungeon, the Empyreal Bridge.

Etrian Odyssey V was well received by critics,[3] and was the eighth highest rated Nintendo 3DS game of 2017 on the review aggregator Metacritic.