This game has a pretty interesting concept, and it basically revolves around the solution of a single puzzle with a bit of creativity and oversight.
Different creatures have different skills (slugs can get across narrow corridors, robots can activate the white panel things, humans can open doors, cats can climb walls), and in order to harness the power of each creature, you have to set up your karma to a specific level so that you'll reincarnate as the creature you need when you die. If you, for instance, kill things weaker than you or kill yourself, your karma gets bad, but if you do other things (like talking to the cat-like thing as a human, for whatever reason), your karma gets higher. So, once you get the mechanics of the game, it becomes a matter of intellect to solve the whole thing.
I just don't understand why the highest karma makes a person be reborn as a tree. Also, more puzzles would be nice, and maybe a less sluggish movement speed. The game has a nice idea behind it, it's just not very polished. The movement is sluggish as hell, HUD is confusing, graphics are bland, it took me a while to learn how the wall climbing mechanics worked, and heck, sometimes it's confusing to know how your actions affect your karma, and sometimes it takes a while to discover how to die according to the creature you're currently living as.
The graphics are too bland and simplistic, it'd help if the HUD actually looked like a HUD, rather than just a sketch of a HUD, and the extremely bland "You win" message after the end of the game is not the reward I was expecting after going through the work of winning the game (a cutscene about enlightenment or something would be a lot better). The music, on the other hand, is pretty intrincate, relaxing and interesting, I quite like it.