>>94165528after that there's short maps that have other game mechanics that allow you to farm specific items/currencies and each mechanics has its own bosses after you farm them that drop strong uniques.
These maps can have random modifiers that make them more difficult but increase the rewards, and you are meant to progress them so the monster level increases and you level up and get better stuff.
This is very addicting in PoE1 since you can spec into what you want to do so you can consistently farm that and make it more rewarding, in PoE2 it isnt that well made yet but I assume they will improve it since its one of the strongest parts of the predecessor.
There is also a postgame storyline related to the Atlas but it's still very barebones in 2, the final boss of it is a cool fight though