What games meet this criteria?

You are asking for Borderlands 2, friend. You're in for a grand adventure.

• Overcooked 1 & 2
• Unrailed 1 & probably 2
• Slay the Spire 2

Don't Starve Together

I think there's actually a lot of games that fit all of those?

What genres do you play? Shooters, survival games, RPGs, sandboxish...? Might narrow down some ideas.

Deep Rock Galactic fulfills nearly all your requirements, depending on A) how it runs on your machine, seems Linux works for many and B) if alien bugs count as zombie for you, as they are also mindless hordes that swarm you. I have a lot of fun with DRG, I can recommend it.

Trine Series contain fun coop puzzler for up to 3 people. Don't know how all of them play on Linux, but 1 & 2 work on the Steam Deck, so should work in general. And 2 is in my opinion the best one. They have a story, but its not really about it, the puzzle and levels are 95% of the focus.

Lara Croft and Tempel of Osiris is up to 4 coop puzzle action adventure. It was fun and the difficulty 9f the puzzles gets adjusted for the player number if I remember correctly. Seems for some it runs on Wine, but as always, mileage may vary.

Try gambling with your friends

Had a lot of fun with Astroneer and Planet Crafter. Both run well on Linux and the steamdeck, so should also have descent hardware requirements. Only the story is a little thin.

Steam search is being a little less helpful than I'd like, but

• It Takes Two / Split Fiction
• Operation Tango
• Timemelters
• Lords of the Fallen

Are all games I've at least heard of before that all have a friend's pass, so only one of you would even need to buy the game

Mindustry is free, low spec, runs on linux, has a campaign - its a factory + tower defense game

Absolum

Kingdom Two Crowns

so I went back to playing star trek online and champions online from cryptic. they are from aroudn 2010 so pretty easy on hardware. you can play together although you may have to do tutorial along although I think with champions if you play at the same time I think you are in the same instance and can play together. I know champions is eventually skippable for an alt but not sure if you can skip from the get go.

Halo.

Unless you count the flood as zombies? 🤔

Baldurs Gate3 Absolum Streets of rage 4

All the action roguelikes seem to fit

Starbound! I fucking love Starbound.

Elden Ring?

Pathfinder and D&D run on a telephone and a handful of dice. And the zombies are optional.

Real talk, though, I'd have to second the recommendation for Starbound. It has tons and tons of mods, and it runs just fine on Linux.

Core Keeper might fit the bill. Very similar to Terraria, but closer to isometric instead of a side scroller. Randomly generated world divided into staggered biomes with handmade "scenes" spawned in to add interesting things to find.

Top of my head.

Trine Series (2 specifically), Terraria, Minecraft or Luanti, Risk of Rain, TF2 MvM, Don’t Starve together, DeepRock Galactic, Torchlight 2, Sea of Thieves (Custom seas), Zero-K, SarCraft 2 co op, Shadow Warrior 2, Crime Boss Rockay City, Payday 2, Gauntlet Slayer Edition, E.Y.E Devine cybermancy, Battle Block Theater, Magicka, Monaco, Cult of the Lamb, Vermintide.

Maybe Mechabellum could be something

it is an autobattler like direct strike from starcraft, easy to pick up, hard to master though

also.. V Rising could be something for you (isometric action hack and slash with building an crafting)

and if you dont mind "overwhelming" systems in the game, warframe could be fun too

There’s a game I’ve seen a lot of YouTubers starting to play over the last week or two that looks a lot of fun - Mecca Chameleon

Online multiplayer. One person is hunter, others are hiders. The twist is that you can paint your character. So you find a hiding spot, and then paint yourself to blend in to your surroundings

I don’t know if it’s what you’re after, but it looks like a lot of fun