Two maps (well, there are three, but the first and the third are identical) with some very interesting physics experiments. The first map has a very useful jetpack built into the second trigger of every weapon. One of the best I've used. The second has some pretty serious weapons modifications... as a solo test level, this one'll keep you coming back for more, and as a net level... well, carnage rates will be pretty absurd. Nicely done, as experiments go. Give 'em a try!