Realm Grinder

I would say its decent. One of the better clicker games for sure.

A rare example of a game that starts out simple, but builds complexity depending on how quickly you can master the earlier mechanics, creating a satisfying experience throughout - as long as you're able to find an efficient path forward. There are points at which you fly through the progression, and times where things slow down and really push you to find the most optimal path forward. The game rewards both active and idle gameplay depending on your chosen factions (which can be swapped easily), with some upgrades only being accessible by spending time offline; but the overall trend is towards automation the deeper you go, as with most good incremental games.
My only real complaint is that the secret in-game achievements are all tied to upgrades, so you're strongly incentivized to look up the requirements online for any which you don't unlock accidentally or figure out yourself; these were fun for community-building when this game first launched on a site for flash games which had forums and chat functions, but with all of them solved it just creates a progression difference between those who look them up and those who insist on not spoiling anything and trying to figure everything out on their own. But that's ultimately a minor gripe which can be resolved in a few seconds via search engine.
Overall, if you want an incremental game that rewards analytical skills and experimenting with builds, with a very long road to completion, this is a great choice. I can't comment on the late game portions yet as I haven't reached them, but I find what's here to be very satisfying. All these years later, and it's still getting content updates!

Ok, so like all idle games this thing is objectively bad, like straight ass. That being said, it is also the best to ever do it (IMO) and I can't say that you shouldn't play it if you have a hole in your head that says to play idle games, like I do. If you have to play an idle, in other words, play this one.

TL;DR: Interesting idle game concept but likely less enjoyable without a guide if you want to progress further without missing stuff.

It's an idle game that certainly has some depth considering what I've been seeing on the internet.
That itself is also the reason why the game felt kind of odd when I first started it. While managing to unlock more upgrades and working on trophies, some things just feel hidden and not highlighted as important when you actually need them.

The gameplay focusses more on swapping your choice of upgrades, every time you restart a run to be more efficient in your global gameplay.
And here lies the biggest problem. Without a guide you will start to question why progress might hit a big bump, likely because u missed something.
That's the reason I'm using a guide which shows me important things for my current progress and tells me about things I could do, might do but not need to or shouldn't do yet. It gives a better feeling of knowing that you will make progress and not constantly bump your head on a wall.

This game is awesome and free. In-game purchases are not at all needed to fully experience it. It's a long play game and worth it. I highly recommend this game.

I keep coming back to this game, over all one of the greatest idle games and its still getting updates

Excellent. I love that there is a cloud save feature. I have been playing the same save file for years.