Toy Soldiers, the original, was a curious blend of tower defense and action gameplay. In it, you could play towers to fend off waves of opponents, but the meat of the game came when you took control of the towers themselves, aiming and shooting to your hearts delight. It was one of the best-selling XBLA titles of the year, so it's only natural to expect a sequel.
Keeping with the theme that the name brings, Cold War takes place in a toybox, where (presumably) someone's imagination has come to life. The aesthetic is a cool one, as you look outside the box and see a room full of clutter appropriate to the era. In the campaign mode, you're tasked with defending your toybox against waves of Soviet armies rushing in for victory. Much like any tower defense game, you need to strategically choose your towers based on the type of enemies that are coming; machine guns have little effect on tanks, and anti-air can barely do anything against ground units, as examples.
The fun comes when you take control of a turret, allowing you to aim and shoot it yourself. Each of the turrets plays wildly differently, with a distinct use for each of them. Some of them, such as artillery, also allow you to guide the shells after firing, just enough to track a target that you may have missed by a metre or two otherwise. Even each turret upgrade can feel different, such as the individual shells of the level-1 tank turret to the rapid-fire destruction from the cannon at level 2.
That's not all that's tucked away in your arsenal, however. First, there are typically one or two vehicles scattered about the battlefield that you can take direct control of, like tanks and helicopters. These run on batteries, which can be collected while riding these engines of destruction (they can devastate entire armies), but eventually the battery will run out, forcing you to wait as the vehicle respawns and recharges. Additionally, from taking control of towers and destroying enemies, you build up a multiplier. Build up enough of one, and you get a barrage. These are one-use abilities that can swiftly turn the tide of the battle, such as an artillery barrage or, one of the most popular ones, a Rambo-like figure that you control yourself, spitting out one-liners and rockets in equal measure as you walk across the lines of combat.
The campaign isn't a long experience, but even if you tire of it (and its extra difficulties that do things like prevent you from controlling towers directly, or remove the tower AI), you can play in other modes as well. These include such additions like a Survival mode, which pits you against a never-ending wave of enemies to see how long you can last as your towers are constantly pelted by bombers, or another mode which forces you to purchase locations before you're able to build on them. And, new to Cold War, if you want you can always just play through the games with a buddy in local co-op, which works quite well. Of course, you could always head into VS mode, too, placing one of you as the Soviets to fight back against the American oppressors.
There's a solid game to be had with Toy Soldiers: Cold War. In building upon its predecessor, it refines the nifty formula that it had, adding new features, modes, and the ability to play with a buddy. If you liked the original, there's really no reason you wouldn't like this one. It's a fun game in its own regard, and though it may not have a whole lot of staying power, it's a good downloadable title that you can drown hours in.