War for the Overworld, a Dungeon Keeper inspired game from 2015 had a huge free upgrade recently bringing some graphical improvements and performance optimizations.
Godfall Ultimate Edition released onto Steam on April 7, a former Epic Store exclusive, and now thanks to the Steam release it runs very nicely on Linux and Steam Deck with Proton.
Oh goodie, more ways to completely mess with the whole galaxy. Stellaris: Overlord has been announced as the next full proper expansion for the popular grand-strategy game from Paradox.
Two Point Studios might be currently working on Two Point Campus but they're not done with their modern take on Theme Hospital with the Two Point Hospital: Speedy Recovery DLC out now.
Techland might have their shiny new Dying Light 2 now available but they're apparently not even finished with the first Dying Light with a big update out now.
Factorio is one game that I've yet to try on my Steam Deck but it sounds like it's not ideal right now. Thankfully
Wube Software LTD. are working on it.
ELDEN RING is the latest game developed by FromSoftware who are known for games including Sekiro: Shadows Die Twice and Dark Souls. It's out now, with a Steam Deck Verified rating - so it works on Linux with Steam Play Proton.
Roguebook, the singeplayer roguelike deckbuilder from the developer of Faeria just got a big upgrade with a new Tournament system, plus a DLC character.
Paradox Interactive has released the 3.3 'Libra' Update for Stellaris, as their "custodians" initiative continues with a dedicated team working on free updates.
Superliminal, the brilliant puzzle game where your perspective changes the size of things you hold to progress recently gained some multiplayer modes - and now they're on Linux too.