Goodnight, Sun

The sun is dying. One billion minds sleep below. You are HALCYON, the caretaker AI — dismantle a solar system, planet by planet, to build them an Ark. An incremental that ENDS: 4–6 hours, two endings, no infinite grind. Every world you consume stays gone. Even the Earth. Especially the Earth.

At a glance

• Platform: Windows.
• Genres: Casual, Indie.
• Release date: Jul 30, 2026.
• Steam user reviews: Positive (91% 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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