El Edificio 25 (Building 25)

Puzzle-box of a game set in a retro-futuristic mansion, with spare but elegant graphics and excellent sound fx. As you explore, you will encounter silent, well-dressed androids, elegant old-world furnishings, dirigibles, teleporters--and sudden violence. You can die here--"undo" will be your friend, especially in the endgame's chase sequence--and one puzzle, evading a relentless killer android, is almost impossible to solve without help beyond the in-game hint system (I recommend the very friendly web forum at http://www.caad.es/foro). All other puzzles are well-clued and cleverly interlaced. A highly polished and satisfying game.