Worms: Ultimate Mayhem is the latest in a 16 year old (!) series from old-school developer Team 17. These guys have been operating under that label for more than 20 years, and are most famous for making - you guessed it - Worms games.
This particular title isn't strictly a new game, per se, but instead it combines content from Worms 4: Mayhem and Worms 3D, with some extra maps and miscellaneous tweaks that are intended to bring it up to date.
I played a lot of both of those earlier games (I still have them, in fact), so I was very interested to see what Team 17 had done to fix the numerous issues the transition to 3D had brought to the series. Before we go into them, though, a quick explanation as to what's going on here for people who are new to the series...
Worms is a turn-based strategy series, in which players take control of a worm from their team of four and must use any of their available weapons in an attempt to decimate worms from the opposing team(s). This all plays out in a physics-based world in which a lot of the fun comes from unintended consequences; accidentally hitting your own guys, sending a worm flying onto a mine which then explodes and causes some more chaos - etc.
With fully destructable environments and physics-based weapons, no game plays out the same way and you have to use your brain to it's maximum capacity and leverage every aspect of a weapon's ability if you want to succeed against tougher opponents. It was, quite simply, rather good.
Originally, the Oligochaeta-themed activity was enacted on a 2D stage, which you observed side-on - like so:
With Worms 3D and Worms 4, however, Team 17 took the action into the third dimension, which mean that you now had an extra axis to consider when firing your weapons. Given each is affected by gravity and wind, this increased the complexity by an enormous factor and made it frustrating to try and hit distant enemies with all but a handful of weapons.
That's still the case in Ultimate Mayhem.
Another problem introduced by the shift in perspective is trying to see what's going on in the first place. In the 2D games, you could track the path of a projectile simply by panning left and right, with maybe a little up and down thrown in occasionally. Here, it's automatic (with some override ability) and almost never manages to show you what's going on at all. It's quite simply one of the worst implementations ever seen of a tracking camera in a 3D environment.
This compounds the aforementioned complexity of actually hitting your targets in the first place, as you can't even learn from your previous shot so as to tweak your technique - you simply don't get to see what happened to it.
It's also got a terrible user interface which completely ignores the standard implementations for such things and requires time and experimentation to understand. Yes, you'll get there, and no, it doesn't take that long to figure out, but you'll still find yourself scratching your head wondering why they went in this direction.
It has a single-player campaign which, in addition to providing fairly standard matchups against AI opponents, also crafts a number of unique scenarios in which you are required to heavily leverage certain techniques (like jumping or using specific weapons, etc). These missions are fun, for the most part, and really do help to hammer home the skill set necessary to fully leverage the techniques in question. It's a good inclusion and is a great way to prep yourself for the real purpose of the package: multiplayer.
Multiplayer makes things more fun in the usual ways (there's nothing quite like shooting a real person's worm off the edge of a map and into the water), of course, but it also helps you to forgive some of the more inane aspects of the execution. After all, everyone else is struggling against the camera and weapons too - unlike the increasingly-likely-to-hit-you AI that don't have to force their will blindly through the porridge that is the interface.
Overall, Ultimate Mayhem is a disappointing experience. Third person camera issues were solved long ago, so a revisit to the days before developers solved this problem is a retro hit we could do without. Similarly, cookie-cutter user interface designs are one-a-penny on any platform you care to name, so to see something so cumbersome - even at a budget price - is another disappointing throwback to a part of gaming history that's best left buried.
Ultimately, if you're looking for some Worms mayhem, we'd recommend sticking to the 2D variants - the recently released Worms Reloaded, for example.