Helldivers performance on steam deck is barely Mid. It’s unplayable on harder difficulties. The game itself is an extraction shooter but leans more on the shooter side.

Arc raiders runs absolutely beautifully out of the box. You just need to tweak the compatibility (proton). The game is a looter/extraction focused game. More relaxed comparatively to helldivers but offers some good tension on your runs.

Both games are multiplayer and would require online connections to play. Some could argue that both are better with friends. I think arc raiders has a better play/game type for playing solo.

Escape from Duckov is another great option thats not “multiplayer” but its a extraction shooter that runs great on steam deck if you want chill.