I like how it is an evolving game with new ways to play with every update and they listen to what the players want and update us on what they plan on doing next. Risk of rain 2 is a good sequal to risk of rain 1 where the first was limited to a 2d platformer, risk of rain 2 expands beyond that limit to bring fresh ideas to the table and a whole new level of live, die, repeat. I am excited to see what the 1.0 will add and what they will do afterwards like make a new game or go even further with two.
Played it a couple hours during a free weekend and it is definitely a timesink (not necessarily a bad thing). Different classes for various playstyles; tons of upgrades along the way (kind of like a Binding of Isaac run x10); and lots of entries to fill up, which all in all could be hundreds of hours of busywork if you're a completionist.
Personally I really liked it, but just haven't found enough free time, which is why it has been sitting in my wishlist thus far. It would be on top of my playlist if I got it for free though
I have a literal ton of fun playing it every time, even when my builds are bad and I die immediately and have to watch my friends get all my items. Multiplayer with friends is one of my favorite aspects of this game.