This game is pretty much what MC escher would have made if he made games, it is a fantastic work of art, it barely should be called a game.
And no, it is nothing like Portal... I keep hearing people make that comparison and lbsh Portals puzzles are simple and very repetitive especially portal 2...This game makes you think in entirely different ways for each puzzle. Other than the fact that both characters can fall forever the games are barely the same genre.