Perhaps not as good but worth playing if you enjoyed the original trilogy. I can't exactly pinpoint why but I don't think I liked it as much as the previous ones, although I had quite some fun with it.
With the same kind of humor, high quality voice acting, strange characters and beautiful 2D graphics, it somehow felt a little less charming. It may have been just the lack of novelty, because I liked the story and most of the puzzles. Things can get a little confusing near the end, but that happens to any decent story involving time travel and it was an interesting way to resume the plot after the trilogy's ending.
More info: https://en.wikipedia.org/wiki/Deponia_Doomsday