Need some critically highly-rated games? Humble Bundle put up a rather fantastic selection of games that IGN gave either a 9 or 10 score to and it really is a good bundle.
To save you clicking around below you'll see the expected compatibility for each title on Steam Deck and Linux desktop, along with any ProtonDB rating and noting any Native Linux versions available. Plus each is a Steam link, so you can go see more info on each if you need to.
Inside the bundle you can get:
Disco Elysium - The Final Cut - Deck Verified, ProtonDB Gold
Wildermyth - Deck Verified, Linux Native
Spiritfarer: Farewell Edition - Deck Verified, Linux Native
GRIME - Deck Verified, ProtonDB Platinum
The Forgotten City - Deck Verified, ProtonDB Platinum
Paradise Killer - Deck Verified, ProtonDB Gold
Chivalry 2 - Deck Unsupported, ProtonDB Silver
+ 10% off (Almost) anything in the IGN store + Three months of IGN Plus
Check out the full bundle here.
FYI: Humble and IGN are both owned by Ziff Davis, Inc.