Start & platforms

Separate a Proton launch from a playable setup.

Evidence checked November 3, 2026 · PC Demo

The short answer

The current Demo does not list native Linux support, and the developer does not guarantee Proton compatibility. One player reported launching it on CachyOS with a particular Proton build, but still could not complete the tutorial’s middle/right-click interactions. A successful launch is therefore not evidence of a fully playable Linux or Steam Deck setup.

Checked November 3, 2026. Current Steam platform listings were checked November 3. The CachyOS result is an October 3 player report, not a test on this site or a Steam Deck certification. These are sourced instructions and decisions, not our own gameplay test.

On this page

One Steam Deck report is useful, but limited

An October 10 Steam Demo reviewer says they played on Steam Deck and describes it as roughly 6/10 playable. That is evidence of one person's partial playability experience, rather than a Deck Verified rating, tested controller layout or smooth end-to-end tutorial.

If you try it, check camera movement, object placement and the required tutorial actions before investing time in a large market. Preserve the exact runtime and input details if a step fails. The older Linux report below shows why reaching the title screen alone does not establish full compatibility.

Check the support boundary first

The separate free Demo lists Windows. The upcoming parent game lists Windows and macOS, but not Linux. In the October 3 Linux Support reply, TheLaba said Linux/CachyOS was not officially supported and Proton behavior could not be guaranteed.

This does not prove that every compatibility-layer attempt will fail. It means you should evaluate the complete input path before relying on the game for a Linux or handheld session. Neither a Windows icon nor work on controller input establishes Steam Deck Verified status.

What the reported CachyOS route actually achieved

Part of the October 3 report	Result or limit
Compatibility build	`proton-cachyos-11.0-20260703`
Runtime/setup	The player described Steam Linux Runtime and installation through CachyOS package tools.
Steam selection	Restarting Steam made the installed compatibility option appear for that player.
Game launch	The player reported that the Demo started.
Tutorial interaction	Middle/right-click input still failed; the report does not establish a completed tutorial.

These details preserve a reproducible historical lead, not a recommendation to install an obsolete build. If you already use CachyOS, consult its current gaming documentation for package availability and setup. Its gaming packages and custom Proton versions are distribution tools, not an Oboro no Ichi compatibility guarantee.

Do not transfer CachyOS package instructions to SteamOS or another distribution without checking that system’s own guidance.

Assess menus and the tutorial, not just the title screen

Record the actual app and build: the Windows Demo is App 5271720, separate from the upcoming parent.
Record your distribution or SteamOS version, compatibility build and input devices.
Check whether pointer movement, menu selection and the tutorial’s requested mouse interactions each work.
Use the documented R rotation and Q/E zoom where applicable, while keeping camera and tutorial requirements separate.
If a required interaction fails, preserve the exact step and symptom rather than calling the setup fully compatible.

No verified Oboro-specific launch flag, Steam Deck community layout, controller-button substitute or universal runtime repair is established by the sources reviewed here.

Choose a next step that matches the failure

For a launch failure, compare your environment with the dated Linux thread and any newer replies. For a top-left drifting cursor, see the separate documented Demo input fix; that is a narrower symptom than all Proton input failures.

If you need a supported Demo platform now, the official listing points to Windows. Keep Linux and Steam Deck as compatibility decisions with unresolved input evidence, rather than purchasing or changing your system on a promise this guide cannot substantiate.

What a useful result looks like

You know whether the game launches and whether required menu and tutorial inputs work. An unresolved report names the actual OS, runtime, Demo build and failed interaction; it does not stop at “runs on Proton.”