Subnautica 2 is playable on Steam Deck, but early access comes with visible compromises

Subnautica 2 is finally available in early access, and Steam Deck players can already dive into its alien ocean. The good news is that the game runs. The less exciting news is that it needs heavy visual compromises to stay stable.

Unknown Worlds had already shown Steam Deck footage before launch and confirmed that the game includes a dedicated Deck preset. The target is a solid 30 FPS, with more optimization planned throughout early access.

In real testing, that target seems realistic. Subnautica 2 defaults to the lowest graphics settings on Steam Deck, with TSR upscaling set to Ultra Performance. With those settings, the game mostly sticks to 30 FPS, with only small drops when swimming too far or moving quickly through the world.

The game still has some beauty on the Deck. The ocean, lighting, creatures, and environments remain clear enough to understand where you are and what is happening. It does not look broken or unplayable.

The main issue is image quality. Because the game relies heavily on aggressive upscaling, the picture can look much blurrier than expected. Shadows can shimmer, sparkle, and appear low resolution. The effect is visible during the day and becomes worse at night.

That kind of visual noise does not completely ruin the experience, but it can be distracting. For a game built around atmosphere, exploration, and underwater beauty, blurry upscaling and shimmering shadows are hard to ignore.

There is some hope, though. The game can still hold around 30 FPS when TSR is raised to Quality in some cases. It can also run decently at medium quality with TSR left on Ultra Performance. That suggests there may be room for better settings once optimization improves.

The battery drain is another concern. Subnautica 2 pushes the Steam Deck hard right now, so players should not expect a light, long lasting handheld experience.

This is probably best treated as a cautious Steam Deck recommendation for now. It is playable, it is Verified, and it can hold its 30 FPS target. But players should expect blur, shimmering shadows, low settings, and high battery use.

The good news is that this is only the start of early access. Unknown Worlds has already said optimization will continue during development. If future updates reduce the blur and improve performance headroom, Subnautica 2 could become a much better Steam Deck game over time.

For now, it works, but it is not the ideal way to experience the game unless handheld play matters more to you than visual clarity.