Nientum - Op.ZERO

A 2D action-adventure where the story unfolds by tuning the stage with music. A play by Aleph and Liora, who have lost their memories. A beautiful yet eerie stage, and the secret of the forgotten theater await. Your choices will determine the play's ending — and their fates.

At a glance

• Platform: Windows.
• Genres: Action, Adventure, Casual, Indie, RPG, Simulation, Sports, Early Access.
• Release date: Nov 24, 2025.
• Steam user reviews: Very Positive (99% positive).
• Delivered as a Steam library entitlement — activation is handled by Steam.

Minimum

Recommended

System requirements as published by the developer on Steam.

Activate on Steam

• Open the offer above — it takes you to this game's official Steam store page.
• Buy it there, or if you bought a key elsewhere, open Steam and choose Games → Activate a Product on Steam.
• Enter the product code exactly as it was issued to you.
• The game appears in your Steam library — download and play.

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