I wonder if there is a game that takes the concept of those KR novels where there is a hard tutorial. I think it would do well as maybe a streamer game kind of like crabgame(squid-game).
Probably honestly. Korea has quite a few games that never really cross borders iirc so if it's anywhere, it's in Korea.
Black desert is a KR game that went global mainstream. You may try that if you want. I dont know the gameplay though.
The idea of levels having different difficulty modes isn't uncommon, like so you can replay a level but with all the enemies having higher stats and more drops and stuff, though having different difficulty modes for a tutorial sort of misunderstands what the purpose of a tutorial is.
The thing about those novels is, the tutorial is way too long for a game. A hundred-floor dungeon! If a hundred floors is just the tutorial, just how long is the game itself?* If you want to enjoy the experience of a KR hard-mode tutorial dungeon as game, try [insert roguelike game here], or maybe one of the Wizardry games. There should be several set entirely or mostly inside a single dungeon. *Though it would be possible in a MMO, have people go through an expanding tower/dungeon and gradually meet other players bit by bit in both pvp/pve events, and then when they reach the top it would be an open-world MMO. Which is more like the setting of Max Level Newbie or many cultivation novels.