Golf With Your Friends literally brings my family together

Not seeing any love for Toejam and Earl Back in the Groove. Reimagining of the 90's Mega drive classic made by the original dev.

Cats Quest 2

Pretty cute game and if one person is significantly better at games, they can carry the team pretty well.

• Untitled Goose Game has couch coop (just bought yesterday on sale for $8.99!)
• (I believe) Gun Bros
• LEGO Star Wars The Skywalker Trilogy

I see lots of excellent responses, but one of my favorite games is never mentioned, so I'll mention it here, it's Out of Space it's essentially overcooked but calmer.

There's a game by Devolver Digital called Heave Ho which is pretty fun. And has a free demo.

What the Golf? is lot of wacky fun. It's not really golf and has like 500 different levels, some wildly creative.

I don't see Out of Space on here. It's pretty fun and challenging.

Goat Simulator is silly fun, especially with kids.

Lara Croft and the Temple of Osiris is awesome since it lets you play up to 4 player co-op.

Vicious Attack Llama Apocalypse is a good co-op twin stick shooter.

Niddhog is so freaking good!

Old Apache Air Assault is neat in coop

Biped is on sale right now: https://store.steampowered.com/app/1071870/biped/

It's very similar to it takes two

There were two isometric Tomb Raider games a couple of years back (Guardian of Light and Temple of Osiris which wasn't as good IMO). You could play in single player, but the co-op mode tweaked the puzzles slightly so you'd need to work together to complete them. And as luck would have it they're both on sale. The first is currently a whopping £1.27 on Steam.

If you fancy going even further back, there was a PS2 game called Kuri Kuri Mix by FromSoft. It may looks like it was made for toddlers, but it was surprisingly tough in places. You almost certainly can't buy that any more, but I'm sure and emulator and ROM site will do nicely.

Best couch-coop games

-= FLOSS games =-

Fish Fillets NG

Battle for Wesnoth

Minetest (websearch: Minetest Split Screen Howto)

-= 80s/90s arcade games =-

Bubble Bobble (lesser: Snow Bros or Tumblepop)

Heavy Barrel or Calibre .50 (lesser: Midnight Resistance or Ikari Warriors) [all need 8-way rotator joysticks]

Smash TV(is twin-stick, but awesome) or Narc

Rampage

Gunforce

Double Dragon

Bad Dudes v Dragon Ninja

Final Fight

Golden Axe

Sunset Riders or Vendetta

Silkworm

Cabal

Top Gunner

Side Arms

Alien Syndrome

Gauntlet

Phogs

This is my Couch Coop To Do List for me and my wife (sorry for bad formatting):

A Way Out Asterix & Obelix XXXL: The Ram From Hibernia Asterix & Obelix: Slap Them All! BattleBlock Theater Biped Bravery and Greed Bread & Fred Brothers: A Tale of Two Sons Remake Castle Crashers Cat Quest II Chariot Conduct Together! Contra: Operation Galuga Cuphead Darksiders Genesis Death Squared Degrees of Separation Divinity: Original Sin - Enhanced Edition Divinity: Original Sin II Dungeon Defenders Dungeon Golf Earth Defense Force 5 Ember Knights Escape Academy Escape Simulator Fly TOGETHER! For The King For The King II Forced From Space Fueled Up Gauntlet Golf With Your Friends Grave Danger Hammerwatch Heroes of Hammerwatch Huntdown Keep Talking and Nobody Explodes KeyWe Knights and Bikes Kukoos: Lost Pets LEGO 2K Drive LEGO City Undercover LEGO Horizon Adventures Lara Croft and the Guardian of Light Lara Croft and the Temple of Osiris Lost Castle Lovers in a Dangerous Spacetime Magicka 2 Mekazoo Metal Slug Monaco 2 Monaco: What's Yours Is Mine Moving Out Nine Parchments Nobody Saves the World Operation: Tango Outward PHOGS! Pizza Possum Pocky & Rocky Reshrined Pode Portal 2 Rayman Legends River Tails: Stronger Together Rogue Heroes: Ruins of Tasos Rooms of Realities Rotwood Sackboy: A Big Adventure Shift Happens Sonic Superstars Spelunky Starbound Struggling Surmount Team Sonic Racing The Adventure Pals The Expanse: A Telltale Series The Plucky Squire The Swords of Ditto Tick Tock: A Tale for Two Tipston Salvage Tools Up! Towerborne Trine 2 Unrailed! Unravel Two Unruly Heroes Untitled Goose Game Voyage We Were Here Together Who's Your Daddy Wizard of Legend II ibb & obb

Borderlands and Full Metal Furies spring to mind.

Don't Starve: Together

Lara Croft and the Temple of Osiris
Lara Croft and the Guardian of Light

Rock'n'roll racing is a fantastic coop racer. I think it's available in a remaster from blizzard somewhere.

Pampas and selene: the maze of demons seems fun

Battleblock theater. Silly coop puzzle platformer

On xbox there’s a Teenage Mutant Ninja Turtles game that’s fun for co-op