I call these kinds of games (roguelikes, terraria, minecraft) "learning curve games", because your peak enjoyment of the game is when you have fought your way up the learning curve about halfway. Once you know everything about the game, it becomes boring. And until you get to that halfway point, it's a lot of trial and error (or looking things up in wikis).

Learning curve aside, most of the gameplay loop in this and most roguelikes is movement / auto-explore, ramming into enemies and healing as necessary. Far less of the "strategic" game people make it out to be, though you can spend time tinkering if you want. Brogue tries to rectify this with more tactical play on smaller maps at the outset - it's nicer but fundamentally you end up doing the same thing.

For my part if I'm going to spend a good deal of time grinding, it's generally more fun to slash and shoot something in the face in real time. But those actions games tend to miss out on some golden moments of random chance, tense decision making or interesting possibilities.

I think this is why roguelites have gotten so popular as they try to bridge the gap. Also the likes of Rimworld and DF that let you pause and unpause, advance time at high speed.

Maybe there's a slash and shoot game with the random generation aspect and pausing/unpausing of a rouguelike?

That would be cool, especially if it was FLOSS.