One of the big problems with the Dark Void campaign is that you are forced to spend a lot of time without a fully powered jetpack. Capturing the freedom of motion and the exhilaration of flight are Dark Void's chief successes, and fortunately, Survivor Missions fully embraces this. This downloadable add-on consists of two large arenas in which you protect three key positions against 10 waves of increasingly challenging enemies. The two environments offer a good degree of variety, providing places for explosive firefights and high-flying aerial combat. The action is brisk and satisfying, though there are some awkward rough edges. Still, there are a few hours of fun here, and challenging modifiers (like increased enemy health) and new achievements increase replayability. Reasonably priced at 400 Microsoft points ($5), Survivor Missions is a good way to squeeze some more mileage out of your trusty jetpack.
The goals of each survivor mission are simple: protect the three structures and defeat 10 waves of Watchers without dying. In one mission, The Battle of Ghen Crag, the structures are located on a large rocky protrusion in the middle of the Void; two are on the surface and one is in an underground chamber. Your enemies assault a different structure in each wave, and you must fly quickly to where the fight is raging. You'll get some aerial kicks as you zoom across the surface, dive down long shafts to the underground area, and then rocket back up to the surface in search of your enemies. The game tries to prompt you with the location of the next wave, but it isn't always accurate, so you occasionally have to search for the skirmish and lose precious time. This can be aggravating, especially if you miscalculate and arrive to find the structure almost completely destroyed. Still, the long passages and rocky ruins offer some good opportunities for daring flight.
Once you engage in combat, you'll likely trade in flight for hovering as you seek out your enemies and destroy them. Gun combat is still solid and melee attacks still feel overpowered, but as the enemies get tougher, it becomes clear that headshots are a more efficient (and thanks to a score bonus, more rewarding) way to quickly dispatch foes. Killing baddies is satisfying, especially when you get in the groove and drive your multiplier even higher. You can upgrade your weapons to pack more of a punch (just like in the main campaign), but you must spend points that are subtracted from your total score. This theoretically poses a bit of a conundrum, but the lack of online leaderboards means that the only reasons to strive for high scores are personal satisfaction and achievements. Upgraded guns make combat much more satisfying, and the extra damage is helpful when things get tough. There are no checkpoints in Survivor Missions, so if you die, it's back to square one.
The other arena, Abyss Canyon, is all about aerial combat. You must defend three survivor transports against Watcher aircraft, flying knights, and even the occasional ground-based behemoth. Your jetpack guns are the only thing you need to worry about upgrading, which is good, because maintaining a high multiplier is much harder against airborne opponents. While there are plenty of environmental objects to fly around, the Abyss Canyon mission feels a bit less varied than Ghen Crag. You can hijack a Watcher aircraft or jump into an AA gun on one of the transports to spice things up, but this arena mirrors a number of situations from the main Dark Void campaign, while Ghen Crag feels fresher and more engaging. If you want to make either arena more challenging, you can set conditions that will add a score modifier, like increased enemy health or more expensive upgrades. Again, there are no online leaderboards, so these modifiers will appeal only to masochists or achievement seekers.
Despite the lack of incentive to strive for high scores, Survivor Missions presents a challenge that is likely to suck you in for a short while. There are occasional audio stutters and minor issues with enemy spawning, but on the whole, the action holds up and offers some good entertainment value. Some may find paying for this add-on unappealing, given that Dark Void wasn't exactly brimming with content despite selling for full retail price. But for a scant $5, Survivor Missions is a good bet for anyone looking to log some more jetpack hours.