In some other topic i know this is partially discussed... But there really is something about certain games or types of games that.... take far more of your time then they should, and are fun somehow... Especially as the game evolves and changes over time.

It's less about being idle, but more about being active for short bursts of time, and letting it somewhat play itself before spending your progress. Is there an end game? Not sure. A number of them don't really have a story, and those that do, well they vary a bit.

Clicker Heroes for example, which i played some years ago has changed quite a bit. I remember getting a few hundred thousand hero souls, now it's... well... quite a bit more... There weren't auto clickers that i really recall, and then clan relics and transcendence were new upcoming things. Now they've more or less gotten sorted out.

Watching the numbers go up. Thousands, millions then.... 2.250e500, numbers so large you can't think of it within the confines of our mere tiny human brains. And yet the numbers keep going up.

Some involve mini games. Click on the object, set things up, move things around, assign equipment. Click to deal damage or to heal.

And then when you get to a point, you restart with a NG+ type mode where you can get to where you were far faster, and go far further than before.

Other than being little time wasters, they are actually fairly well done. Well... some of them...

Idle games also... seem to have quite a bit of humor built in. Guess it doesn't hurt to be a little funny and silly :P

I played those games somewhat excessive a few years ago. They are like crack and heroin combined to me. They trigger all the wrong things in me and keep me going for days and weeks, spending hours upon hours micro-managing those games. But with an intervention and a court-ordered rehab, I am nearly fully functional again.

They can be addicting... and yet i stop sometimes and ask myself 'what am i doing?'. I think i only played a month before a few years ago before dropping all idle games, gotten my fill at the time; Happens when progression starts getting too slow. Heh, that's only due to that i haven't unlocked the offline production (which i could now), and this isn't a computer i leave running 24/7. Otherwise i'm sure it would be far higher. Using a custom set, or rather 2 ints you could do it. One dedicated to the exponent and one to the digits, and you only need 6-8 major digits for it. But not sure about the headaches involved; doubles, or reals (80bit) would be needed at least.

Regarding 128bit types... i wrote an Arbitrary Int type for D. Think BigInt, except stack-only and no memory allocation (struct & fixed), allowing you to use it as a built-in type. Auto promotion/demotion as well involved when possible. But without more tests and getting it in phobos, not sure... A number of games have near infinite growth. Dark souls for example you can keep going NG+ and keep fighting harder and harder monsters. And Diablo 3 when i played (on console, 360) monsters & items are based on a level multiplier. (Having the identical item in name but having one 30 levels higher makes it annoying to try and get balanced gear).

Tried Spaceplan?

https://store.steampowered.com/app/616110/SPACEPLAN/

I think I'm done with idle games. I used to have some fun with them, I must admit some of them are nicely polished but something must have changed in me and I don't have fun anymore

Every new idle game that I played, I played less and less. And at this point I don't think I will ever play them again.

There's always a point in some games where I realize either that I am not having fun, rushing to finish the game, or that it is just supremely pointless. To me, idle games fall into the latter. You start off by clicking a ton, then have something that adds your clicks, then ultimately the game will play itself. And that's pretty much it. I guess I can see the fun in optimizing your clicks, but I'd rather play factorio and such for that.

I hate rust: The programming language, iron oxide and the fungus that grows on raspberries (http://greencommons.de/images/7/70/Himbeerrost_Teleutosporen_Lupe.jpg).

The concept of idle game is fun, once. As : one game.

It's also the easiest, cheapest, laziest game concept to milk and re-skin eternally. And I cringe every time a new idle game copies the former one (but in spaaace, or whatever), trying to reframe it vertically, horizontally, or whatnot.

So I did a few of these. The (original?) candy farm one, then cookie clicker, then idle heroes or what it's called. A bit of capitalist venture and some other idle heroes clones. For a while I had the curiosity to check out how they got re-flamed, so I dabbles in idle raiders and a few other kongregate ones. But now my opinion is pretty much cemented. I grew a certain antipathy for the concept.

It's a similar experience to hidden object games. Actually, I was even thrilled by the first ones, the mystery case files ones. Now, the avalanche of samey games illustrates how uncreatively the concept can be milked. It dilutes and drowns the fun idea of the first ones. And now I really see as phony the people behind all these mountains of derivative versions.

So there. Hidden object, idle games ? Amusing concept, play one some day. But as a genre, I see it as borderline scam. In the case of hidden objects, just because it's the same recipe re-applies soul-lessly. In the case of idle games, there's the additional element of trying to hook people on carefully timed "rewards", which is in itself interesting to deconstruct, but feels more about cold manipulation than about sharing pleasure.

On the plus side, though, a running idle game (a non too clicky one) can bring a bit of fresh air to the background when you're working too much on a computer.

I've only played the free prototype version, but even that's a great game :
http://jhollands.co.uk/spaceplan/
especially since you can actually complete the game in an hour or two.