I've wanted a worthwhile first person roguelike for a very long time. Delver made a helluva comeback to become exactly what I was looking for. That is to say it's not only a helluvan example for first person roguelikes, but it's also one of my favorite early access success stories. I went from never wanting to touch the game again to getting that magical "one more run" feeling once the game was released.
Plenty of immersion and atmosphere. I love it when it actually feels humid when I'm down in some dank video game hole. Lot of early struggles until the right combination of weapons drops and then you start moving through the levels all godlike until the game smacks you back down. I know I can get farther next time. Thanks for the damp pixels, Delver.