boardgames

These three are extremely simple and fun:

Ghost Blitz

The Mind

Skull

I'm not sure it falls into your category but skyjo. It is a tiny bit complex and while a game is short one usually does play a series of games tracking points. But single games are totally fine too imo so maybe it qualifies.

What I have come to love about the game as a dad of two is that the game can be paused and picked up with zero downside. The game has no hidden information one can know and no information to keep track of. No past plays to remember or anything. If you know the game I could sit you down at a table mid game, tell you nothing but whose turn it is. And you could continue playing as if you were there from the beginning. It's great if you are interrupted by the kids, cats, dogs, door bell, mom calling, house on fire, ordered pizza. That makes it such a nice game got parents imo.

• Auction games are amazingly good in delivering simplicity and excitement! High, Society, For Sale, You‘re Bluffing!
• Trick taking games are my close 2nd! High replayability and I love the after-talk: The Crew, Claim, Skat are a few examples.
• But sometimes you want to show off and bring more than a card game to the table, that‘s still simple and fun! King of Tokyo, Camel Up, Cascadia come to mind.

Saboteur is really fun card game. Is simple , has team building gameplay and also betreyal plus a point system.

When I played we where 12 , so a lot of people can play as well.

The simplest I can think of is Strike. You are throwing dice into a pit and hope for the best. You do have some control in trying to hit other dice to change their value and you have push-your-luck decisions to make. We sometimes use it to decide the first player in the real game.

Zombie Dice and Martian Dice are some other simple dice games I like. And since OP mentioned Spot It I will throw in Spots, a newer game, don't have a physical copy yet but had a lot of fun with it on BGA.

Outside of dice games I like Bandido a lot. If you look at the components you can probably figure out what to do without reading the rules. Works solo or co-op. Another one: Illusion, you are simply comparing which card has more of a given color.

Our group got REALLY into Love Letter. It was supposed to be a filler game but sometimes we played for hours, especially after a thinkier game.

Eventually we got a bit burned out but then they released Lovecraft Letter and boy did we get right back into it. It felt like a refreshing expansion of sorts.

Didn't have much success with the more casual folks, tho, not everyone likes to "accuse".

Werewords is twenty questions mixed with werewolf. If you played werewolf, you understand the rules immediately. The app takes care of dealing with the hidden information. So it's really simple. And every time somebody says "we'll play a couple of rounds before going home" I know I'm staying for a couple of hours, because two rounds turns into twenty really easily.