Another vote for deep Rock galactic.

You will need games that have crossplay between PC and Xbox One so you can play together across different platforms. Multiple people have suggested Left 4 Dead 2, but that doesn’t have crossplay. Most of the shooters I personally play don’t have it, but there definitely are shooters with crossplay.

Here are my recommendations that have crossplay:

• Borderlands 3 — Collect wacky guns, travel the universe, and shoot bad guys together. The previous games in the series don’t have crossplay.

…Yeah, that’s it for crossplay shooters I recommend. For crossplay games that aren’t shooters:

• Overcooked! All You Can Eat — Chaotic co-op cooking. Work together to prepare, cook, and serve food in increasingly absurd scenarios: in the middle of the highway, on an iceberg, in a hot air balloon that crashes into a different restaurant.
• Ultimate Chicken Horse — Platformer where you build the levels together and then race to the finish. You only score if someone died, so you need to make the level extra dangerous.
• Moving Out 2 — Goofy co-op game where your group plays as a ridiculously reckless moving company. Carry furniture from the house and shove or throw it into the truck. No one will notice if you break all the windows.

If everyone is on PC, things will open up a good bunch. Old-school networked games generally still work. You can go FFA deathmatch in your old favourites or in newer arena shooters, like Warsow or Disco Dodgeball.

First thing that comes to mind is Warframe. It’s a co-op third person looter-shooter, with full crossplay, so you can all party up across your platforms. It’s all very controller friendly, with lots of shotguns, SMGs, melee weapons and space magic that are all really forgiving of imprecise aim. It cares less about twitch reflexes and more about movement.

The scifi setting and “space ninja” aesthetic may or may not be to your taste, although I promise if you take the time really sink into the world it’s actually one of the most refreshingly different and unique scifi settings out there. There’s a lot of weirdness, but as you dig deeper into the story that weirdness all makes sense. And, like, it’s the good kind of weird if you get me? Stuff that makes you go “Holy fuck I want to know what the deal with that is!”

It does have a lot of MMO elements, so it can get grindy at times, but in my experience it’s a really solid game for hanging out and chilling on Discord together. Plus the game itself is free, with no paid DLC or add-ons, and for an adult with an income a few bucks here and there skips a LOT of grind, especially if you check out the third party market website where players will sell you a lot of the rare drops you’ll want for less than a dollar.

Added bonus, it’s made by the original developers of Unreal Tournament, Digital Extremes (there are actually a bunch of UT references squirelled away in the game).

I’m a huge fan of Borderlands so would recommend that and I’m also a huge fan of Halo, the Master Cheif Collection is an absolute bargain considering what you get. Your brother with the Xbox will need to get Game Pass of some sort to join in for any games that are not free to play. Halo Infinite is free to play and has a PvE game mode, if that tickles your fancy.

Going to go out of the shooter box here and say Valheim. I am pretty sure it’s cross compatible with xbox and pc/steam deck. Might not be the thing though if you are just all wanting to pvp, but thought I would throw it out there.

Civ 5 was great for this. Me and another old fart in our 40s played it against each other.

Every year I enjoy the hell out of Left 4 Dead 2 around Halloween. If you guys have never played it, oh you’re in for a fun time. Super cheap and runs on a potato at this point if your Xbox brother can find a computer.

Enshrouded, Chained Together, Payday 3, Risk of Rain 2, Helldivers 2

The Quake games (1 and 2) got updated with co-op support and cross play.

Palworld is another kind of game playable multiplayer on xbox/pc.

Here’s a full list of crossplay Xbox and PC games. I figure if it’s on the pc, there’s a good chance it could be played on the steam deck as well.

Notable mentions in there that I’ve played and enjoyed are Destiny 2, Overwatch 2, Remnant 2, Left4Dead 2, (I’m seeing a pattern here), and Deep Rock Galactic.

Some games that make for some fun coop and don’t require a ton of screen time. All of these are at least gold rated on ProtonDB so should be fine on the SteamDeck, though I’m not sure about crossplay with consoles on any:

• Sanctum - An interesting combo of first person shooter and tower defense (Sanctum 2 was also real good)
• Borderlands 1 - Looter shooter with some solid humor (Borderlands 2 was also real good, but goes downhill in later games)
• MechWarrior 5 - Who doesn’t want to be a giant mech riddled with guns?
• Left 4 Dead 2 - Fight together to escape zombies, or in multiplayer servers work together as the zombies to take out other humans

Now, less of a focus on shooters:

• Golf It and Golf With Your Friends - Put Put golf taken to extreme levels
• Magica 2 - Murder enemies together in a top-down wizard game
• BattleBlock Theater - Jump over obstacles and solve puzzles together

Helldivers 2 is an awesome game for this as it’s very cooperative and is also a shooter. Though you do need either a pc or a ps5 for it so I’m not sure if you can play it.

Strategy games are great for busy adults imo. I like either Civilization or Factorio because you can compete or collaborate as desired, and in as much or as little time as you want.

Apparently I was the only one to read the title that way, but I thought your brothers died (late) in their 40s.