Pretty solid, but tough platforming. The full-screen mode doesn't really work that well, though. Graphics were pretty good, and the sound fit nicely, though it took a while to load in.
The two biggest issues I had were that the game hangs for a bit when you enter an area for the first time, and that the boss doesn't really have a lot of feed back. I don't know whether I'm damaging the boss or not, and how much health it had left. I wasn't sure if I was doing anything right.
The ladders also felt very weird for me, I couldn't really get why I could/couldn't land and climb on a ladder when cloaked or uncloaked.
Quite good overall, though.