Tom Clancy’s Rainbow Six Vegas 2 is the perfect example of what a sequel should be. Developer Ubisoft Montreal took great pains in making sure they didn’t mess with the stellar qualities of the original, adeptly adding depth and diversity to this here sequel. A simple formula that many developers fail to adhere to: leave the good stuff and add better stuff -- often it's change for the sake of change, for better or worse, and usually worse.

New, for example, you can now sprint. Not a radical modification, but when you have to get across the expanse of a warehouse with no cover and five enemies looking to bring you down, it's a small but significant game mechanic. The sprint function also comes in handy when one of your buddies -- AI or real -- is down and you need to get to him forthwith for a nice injection of heal juice. Too, the pace of the game seems to have quickened and you often feel compelled to sprint because of the action taking place. Running or sprinting is a mainstay of typical run & gun action games, though Rainbow Six was heretofore rather famous for its intentional tactical lethargy, which remains, but now with a greater sense of urgency to it all.

Another new and similarly subtle change is found in the fact that "leveling up" -- earning rank, skills, and weapons as reward for your time and efforts -- occurs regardless of mode, online or off. So unlike, say, Call of Duty 4: Modern Warfare where you might play through the entire single-player campaign and achieve the rank of General only to find that when you take it online you're back to buck Private and must start the process anew, yet you're surrounded by buff Colonels who have been playing and leveling-up online only, ready to hand you your newbie butt that isn't truly a newbie butt save for some arbitrary code that declares you're new to online so you must be new to the lot of it, which is stupid, Vegas 2 lends itself much more appropriately to skills and tools learned and earned anywhere and everywhere, online and off, so a level playing field for all. To wit: Vegas 2 rewards your abilities to play, not your abilities to stay up all night jacked into a server killing no-lifers so you'll have a new laser sight by morning.

The coolest upgrade by far, however, is the level design of both the multiplayer and single player maps -- especially the single player maps, in fact. Conventionally, multiplayer levels of sequels get the lion's share of overhaul, as that's where any given game has legs, with the live, real-people online stuff. However, Vegas 2 has a lot of varying, non-linear paths and obstacles for the single player campaign, too. If you want to see what top quality level design looks like look no further than this game. On one level, for example, you can send off your AI cohorts in on the ground floor while you head up to the roof to cover them by sniping enemies, then come through the ceiling and meet up with your team again. That's level design normally found in multiplayer, but it's a single player design principle in Vegas 2 too, making the whole package all the more compelling.

Other sequel tweaks include a dozen new weapons and a new jump in/jump out cooperative mode which lets a buddy join your game anytime -- a cool feature but questionable since the original game offered four player co-op... perhaps underutilized in retrospect, as if the developers realized that most people don't have four friends they can play with on a regular basis, what, with school, work, and "real life" and all that stuff getting in the way. Also curious is the fact that only one player can control the AI redshirts. Sharing of this mechanic might have made for some more interesting online gaming. On the plus side, the multiplayer modes are as good as ever with three new modes: team leader, total conquest and demolition. Of the three, team leader’s elimination style play is as good as it gets for multiplayer.

When you add it all up, what you get with Rainbow Six Vegas 2 is a rock solid sequel to a rock solid game. It looks and sounds better than the original, as you'd expect, but it also looks and sounds better than most any other game currently on the market. Clearly the developers at Ubisoft went back to the playbook for this one, but just to study, not to overhaul, and then came up with some great new additions and worthy tweaks. Not broke, not fixed, just enhanced in all the right ways.