This game is ridiculous. The proportions are simply unreal.
At the time of writing this, I have 170 hours of play, and well over 160 of these were played thanks to steam familly share. Isaac is a "roguelike" of sorts, much like Enter the Gungeon, every run begins with a blank slate, and you get to collect power ups and see how their effects interract with one another. Some combos are simply broken. And I don't mean "overpowered", no, I mean you'll escape the game's normal limitations with the right items. If for exemple, your character's health points are coins, what would happen if you had an item that dropped a coin everytime you get hit? Just a small one, which not only can but did happen to me more thna once. Without even realizing it, before I had spent even a cent, I had already begun making dozens of runs with each character to get every possible completion mark. I was already familiar with almost al the items and which ones not to put together unless I wanted to destroy my run... and I still hadn't bought the game!
I still haven't completed even half of the entire game by now, but I finally bought it for myself.
It was high time I supported the devs, considering how much I played this game.
As expected from a game of this genre, the replayability is very high, but even moreso than the average roguelike.