Rebellion are set to release Atomfall on March 27th, their survival-action game inspired by real-life events set in Northern England. The good news is that it's Steam Deck Verified already.
https://www.gamingonlinux.com/2025/03/atomfall-from-rebellion-is-steam-deck-verified-ahead-of-release/

For classic Counter-Strike fans, you may want to keep an eye out for the just announced CS:Legacy from the team behind CSPromod. This is not a mod but a full game due out sometime in Early Access in 2025.
https://www.gamingonlinux.com/2025/03/cslegacy-announced-as-a-full-standalone-remake-of-counter-strike-1-6/

Initially Ubisoft said it wouldn't be supported, then they said it would be and now Valve have said that Assassin's Creed Shadows is Steam Deck Verified.
https://www.gamingonlinux.com/2025/03/assassins-creed-shadows-is-steam-deck-verified/

Paradox have announced Crusader Kings III: Chapter IV, the next expansion pass for their popular strategy game. One DLC is already available, with the next major expansion due out April 28th.
https://www.gamingonlinux.com/2025/03/crusader-kings-iii-chapter-iv-announced-with-next-major-expansion-in-april/

NVIDIA have released NVIDIA RTX Remix, their modding platform that allows developers to enhance games with full ray tracing. Additionally, Half-Life 2 RTX is getting a demo on March 18th.
https://www.gamingonlinux.com/2025/03/nvidia-rtx-remix-released-plus-half-life-2-rtx-demo-arrives-march-18-looking-way-too-bright/

Warhammer 40,000: Space Marine 2 was clearly a big success, so much so that Warhammer 40,000: Space Marine 3 has now been officially announced as in development.
https://www.gamingonlinux.com/2025/03/warhammer-40000-space-marine-3-announced-and-in-development/

Ah hell, here we go again, I'm going to be hooked on it. FuturLab have revealed PowerWash Simulator 2 is coming and it will be this year too.
https://www.gamingonlinux.com/2025/03/powerwash-simulator-2-announced-for-release-in-2025-with-split-screen-co-op/

Originally revealed back in 2022, KONAMI have now properly lifted the lid on SILENT HILL f and graced us with a new trailer.
https://www.gamingonlinux.com/2025/03/silent-hill-f-has-now-been-fully-revealed-with-a-new-trailer/

Pocketpair have announced that sometime real soon you'll be able to team up with players across different platforms in the popular monster catcher Palworld.
https://www.gamingonlinux.com/2025/03/palworld-is-getting-crossplay-in-late-march/

Just announced from Red Thread Games (Dreamfall Chapters, Draugen, Dustborn) is Hello Sunshine, a mysterious survival game where you're following a truly massive robot and keeping to their shadow to not get fried by the sun.
https://www.gamingonlinux.com/2025/03/hello-sunshine-has-you-walking-in-the-shadow-of-a-giant-robot-so-youre-not-fried-by-the-sun/

Bazzite Linux, a popular choice for people wanting to put Linux on their handhelds or living room PC, is getting two new editions designed to help developers.
https://www.gamingonlinux.com/2025/03/bazzite-linux-announced-two-new-editions-designed-for-game-developers/

In a surprise turnaround after previously stating the Steam Deck would not be supported for Assassin’s Creed Shadows, Ubisoft have now said it actually will be.
https://www.gamingonlinux.com/2025/03/ubisoft-announce-steam-deck-support-for-assassins-creed-shadows-at-launch/

Chudo-Yudo Games are working on Machine Mind, an interesting mixture of strategy and action genres blended together. There's a demo available to try with Linux support, along with an expanded playtest.
https://www.gamingonlinux.com/2025/03/machine-mind-blends-real-time-action-with-survival-and-rts-elements-to-make-a-fun-mix/

Wadjet Eye Games have announced their next game, the time-travelling adventure Old Skies, is now set for launch on April 23rd.
https://www.gamingonlinux.com/2025/03/time-travelling-adventure-old-skies-from-wadjet-eye-games-arrives-april-23/

Running With Scissors along with Flat2VR Studios and Team Beef have announced the chaotic action game Postal 2 is coming to VR with a completely overhauled experienced. POSTAL 2: VR sounds like a lot of fun.
https://www.gamingonlinux.com/2025/03/get-ready-for-some-chaos-as-postal-2-vr-has-been-announced/

Looks like we're set for a bunch more interesting game reveals! The Triple-i Initiative gaming showcase has announced a return for 2025 and it's likely another good one.
https://www.gamingonlinux.com/2025/03/the-triple-i-initiative-gaming-showcase-returns-for-2025-with-a-teaser/

From developer 8BitSkull (BORE BLASTERS, Void Scrappers) their next game is Skull Horde, an auto-battling dungeon crawler where you raise up an undead army while floating around.
https://www.gamingonlinux.com/2025/03/first-trailer-live-for-skull-horde-where-you-command-an-army-of-dead-soldiers-as-a-floating-skull/

Inspired clearly by the likes of classic Zelda and the Game Boy Color, Isle of Reveries is one for fans of retro games that want something new and fresh.
https://www.gamingonlinux.com/2025/03/isle-of-reveries-looks-like-a-fun-classic-zelda-like-with-some-interesting-game-mechanics/

One of the co-creators of the popular Roll20 virtual tabletop Roll20 has revealed Wyld Land, a free to play bullet hell MMO.
https://www.gamingonlinux.com/2025/03/roll20-co-creator-reveals-bullet-hell-mmo-wyld-land-with-a-demo-up-now/

Paradox and Colossal Order have announced that to celebrate the 10th anniversary of Cities: Skylines that both the original and sequel are getting updates (and of course more DLC).
https://www.gamingonlinux.com/2025/03/cities-skylines-10th-anniversary-will-bring-updates-and-dlc-for-both-games/