The artifacts are a great and fun tool, the worlddesign is nice and some bosses are really unique and excellent. Also playing around with the different Combat-movesets is very nice. On the downside about the last third wasn't as interesting, the fights and loot get a bit repetetive.
The atmosphere and music are really great. The gameplay is overall ok, but consist mainly of sneaking and of avoiding rats, later on a bit fighting. The story is nothing special, but the characters are well-made. With about 12 hours of playing time and no real replay-value it feels a bit short for the price.