Probably not what you are asking for, but the character creation process in the Traveller ttRPG is a great mini game. You basically take a person from 18 to however old you want, and their life path is dictated by your choices and random dice outcomes. It’s a lot of fun. You can end up with a retired admiral, a prisoner or criminal, psionic, etc. Going through this process with a table of friends let’s you build in rich fun connections along the way. The actual RPG then starts with mature, connected characters with a history, instead of 4 randos meeting in a tavern. In the classic Traveller you can even die in character creation. Current iterations removed the death component but you can be maimed from accidents in your career and start the game with a mountain of medical debt.

I thought of another one. There is a minigame in Xenoblade Chronicles 2 called Tiger! Tiger that is great. it is basically an arcade game where getting certain scores gives you credits that can be redeemed for upgrades for some characters. The minigame is randomized and has three different difficulty tiers and is overall really well done.

I hate minigames, the only one i tolerated was Gwent in Witcher 3.

The minigames in shenmue/yakuza. They are literally full games.

I have a love/hate relationship with Nethack’s Sokoban levels.

Not a minigame, but Maniac Mansion being within The Day of the Tentacle is probably my fav.

The full 4K version of Timesplitters 2 inside Homefront: The Revolution, but you have to play something like 75% of Homefront to reach it. I’ll reach it one of these days.

Maniac Mansion: day of the tentacle includes the full first maniac Mansion game on weird Ed’s computer in the room with him and the hamster

EverQuest /gems and /pizza

Don’t know if it would count since it’s used in a couple levels, I think, but PVZ Reflourished, Caliginous Carnival. The levels where you essentially have to pay attention to the zombies beneath the hats and guess which is the weaker one in order to make the spawns easier to deal with. Rinse and repeat multiple rounds until you win. Would absolutely love to see that done more.

Also, along the lines of PVZ, iZombie is definitely up there for my favorite minigame in the series and in general. It absolutely sucks both versions of PVZ2 killed it (unless I’m wrong and the Chinese version still has the old PVP mode, but even then wasn’t nearly as fun as the original minigame, nor anywhere near as balanced when half the time you’d find other players had level 4/5 plants that instantly destroy everything in 0.001 nanoseconds).

Arcomage of course!

It’s always fishing.

The surprisingly deep copy of Balatro in “Dave the Diver” is pretty good.

The tile placement game in Satisfactory is worth a mention. I never fully understood the points system, so I never really rode the game to decent scores, but it was a fun break from the vast size of the rest of the game.

The mini pinball game, at the top-right of the Family Guy pinball table(2007).

It is fast paced and well put together.

I loved the Chao Garden in the Sonic Adventure games.