A fun idea for a nice casual puzzle game: Pixel With Your Friends has released with Linux support where you restore artworks pixel by pixel for a museum.
This isn't your classic Tetris, this is Hexis, a block-falling puzzle game about building up your high score but the blocks will come from all directions.
Build various contraptions in an almost Zachtronics-like automation puzzle game, Captain Contraption's Chocolate Factory is quite reasonably priced and is available now with a demo you can try too.
Cyan Worlds Inc recently released the brand new Riven that's a re-imagined, and expanded version of the classic from 1997. It had a bit of trouble with videos on Linux / Steam Deck though.
In the game Prickle you play as a hedgehog dad trying to collect all your children, as they've done a bit of a runner so you need to stick them all together and get them back home.
OutOfTheBit are currently working on Nanuka: Secret of the Shattering Moon, a cinematic puzzle platformer after previously releasing the positively received Full Void.
Planetiles is an absolute puzzle gem from developer MythicOwl (Hexologic, Harmony's Odyssey) that gives you a wonderful blending of gameplay ideas from Tetris and Dorfromantik but on a mini-planetary scale.
Since I'm a big fan of stuff like Dorfromantik I've been keeping an eye on TerraScape, which just added controller support and they say Steam Deck support is planned too.
Eyebrow Interactive have given a fresh coat of paint to their 2012 game Closure, thanks to bringing in game porter Ethan Lee to get some technical issues sorted out.