Hades presents itself as a roguelike — repeat runs, incremental power growth, procedural variation. The true ending is not unlocked by defeating the final boss once. It is unlocked by defeating him ten times and having a specific conversation with Persephone each time, across multiple in-game seasons. The game’s story does not conclude until the tenth clear.
The surface, when Zagreus finally reaches it with the family restored, is the game’s most visually gentle environment — green grass, open sky, soft music. Zagreus has never seen open sky. The emotional payoff works because the game has spent forty-plus hours establishing his claustrophobia and his need to understand why his mother left.
What the surface reveals: Persephone left voluntarily. The circumstances of her departure are revealed gradually through those ten post-clear conversations. The truth involves Zagreus’s birth, a deal with the Fates, and a history that neither Hades nor Persephone wanted him to know. The game’s entire premise — Zagreus running from the Underworld to find his mother — is built on a foundation of protection through absence.
Supergiant Games structured the ten-clear requirement so that players who have fully engaged with the gameplay loop are the ones who receive the narrative resolution. The ending is gated behind mastery — not because the content requires mastery, but because the story requires the player to have invested enough runs to understand what the running cost Zagreus.

Really fascinating breakdown — I had no idea this was hidden in plain sight the whole time. Going back for another playthrough immediately.
The amount of craft that went into hiding this detail is remarkable. Pure game design artistry.