This is a very fun surprise, Effulgence RPG is an upcoming party-based sci-fi role-playing game rendered entirely from text symbols arranged in 3D space. It looks like nothing else I've seen before, it really is quite impressively made.
A demo is live ready for Steam Next Fest, so you can try it out and see for yourself just how cool it is. A fun idea for a game visual style but the gameplay mechanics are interesting too. In Effulgence RPG, enemies are more than obstacles - they're also raw materials you need. Destroying them breaks them down into particles allowing you to forge weapons and gear using a signature matter printer system, all while exploring a world built from shimmering text characters for a unique, high-contrast 3D ASCII visual identity.

Direct Link
In the press email they noted: "Effulgence RPG runs great on Steam Deck via Proton, with a controller-first UI, readable 3D ASCII rendering on the handheld display, and no platform-specific blockers. That same Proton compatibility also means the game runs on Linux desktops (e.g., Steam on Ubuntu/Arch) with gamepad, mouse, or keyboard. We welcome Linux coverage and feedback from Deck users."
Nice to see! And I can confirm it works beautifully on Desktop Linux (Kubuntu 25.10) with Proton 9.
Definitely a demo you need to try.