Essentially a series of extra missions for 'Rainbow Six', this adds some extra weapons and an extremely useful 'crawl' function, the omission of which stuck out like a sore thumb in the original game. The extra weapons  (some sniper rifles, a new shotgun, many more assault rifles and some  Desert Eagle pistols) are nice to have, but as with the original game you  will almost exclusively use your trusty, silent MP5SD5. It has all the  strengths of the original - palpable tension, some great mission designs -  with some effective new locations. The wrecked, rain-lashed Kosovan city is  extremely atmospheric, and there's an obligatory passenger jet-liner  hostage crisis, too.