I have been really into Antimatter Dimensions recently (
mobile link on play store is the recommended way to play, also available in a less updated version
online). It's probably the best idle game I've played yet. For those unfamiliar it's a free to play idle (optional ads/purchases on the app but the game is totally balanced around never using them) inspired by idles such as Universal Paperclips and Derivative Clicker. It has many prestige layers, ever evolving mechanics and some very large numbers. There's a lot of reasons I like it:
* Allows built in automation of tedious tasks, gradually unlocking more and more automation as you progress
* It's not a clicker game. Mashing isn't going to help you here. Much, at least, there's a very small number of places it might get you an achievement early.
* Keeps things fresh by introducing new mechanics fairly frequently, without those new mechanics then completely dominating and taking over the game. Previous mechanics keep being relevant pretty much forever to some degree, and everything builds on it.
* Is more than just a "numbers go up" simulator at many points. You have to keep making changes to your setups to progress at a reasonable pace, and to fully optimise things you have to have a good understanding of the game's mechanics. There are always choices to make, without being overwhelming in how many things you have to do.
* For the most part, the game supports both an idle and an active playstyle. Just want to leave the game AFK for the most part and check like once or twice a day? You can do that. Want to constantly micromanage to maximise progress? Yep, that's often rewarded with faster progression. Some parts of the game are always more idle and others are always more active but most stages give a good mix.
* Surprisingly active
Discord community for an idle game, with tons of help if you get stuck - or just wanna chat about the game.
* People speedrun it. No seriously, there's a guy on the discord who has "finished" the game in under 7 days. I say "finished" because the current endgame is e4000 EP and all achievements, and one achievement requires you to play for 8 days, which... yeah. But there's a few people who really try and push the game to its limits. Most people will take around 60+ days without guides on a first time through, and over a year isn't unusual if you're not very active.
* Lots of humour in the achievements and newsticker.
So yeah, if you've not played Antimatter Dimensions IMO it's worth a shot.