Zombie Army Trilogy began life as standalone downloadable content pieces for Sniper Elite V2 on PC. The initial release was a fun diversion that saw Adolf Hitler summoning his own army of zombies to help defend an almost-defeated Germany in the final days of World War II. A second edition that followed on from the storyline of the first was released a few months later and now, almost 18 months after that, a third part of the story has been added to round things off, with the whole thing being bundled up into one package and launched on current-gen consoles.

Indeed, when you first fire up Zombie Army Trilogy, it has the feel of a game that is running on a not-particularly-fresh engine. There are countless instances of graphical tearing, some frequent framerate drops, and a lead character that sort of slides across the ground, rather than taking meaningful steps. However, during those opening exchanges, you'll probably still feel as if there's a good bit of fun to be had. Blowing away the horrid Nazi zombies using any of your three weapons is undeniably enjoyable, whether you're using a long-range scoped rifle, a powerful short-range gun, or your sidearm. Grenades, TNT, and land mines are on offer too, all of which work well enough to be viable methods of attack against the zombie hordes. Trip mines also form a part of the arsenal, although these don't work as well as they should. Often you'll only want to set your trap so it runs from one side of a hallway to the other, but the game forces you to use the full length of the wire, meaning that not only do they take an unfeasibly long time to set up, but that you'll rarely get them set in a way that makes any sense.

But, as we say, taking out the zombie hordes is generally a fun thing to do, initially. Slowly though, that feeling fades, due to the fact that you soon realise that although there are fifteen stages of campaign content that can be taken on in any order here, every level looks and plays very, very similarly. It starts out quietly, then zombies appear and you clear them away, then you reach a safe house and stock up on ammo à la Left 4 Dead. After this, there are generally a couple more sections of clearing zombies, followed by another safe house and then - if you're lucky - a stronger enemy or a sniper or two to take on before you hit another safe house and the final boss and his minions. There's little to no variation from one level to the next, and it makes starting another hour-long level after just having played for an hour feel a little bit like a big ask. Especially when you consider the many scripting issues that most levels exhibit. "Defend the Station House" is your goal, so you kill every single zombie that appears (which is the goal of every assault section, even if you have to wander halfway back through the level to find the last stragglers) and then…nothing. You wait, and you wait, and you wait, and then eventually, the next objective occurs.

And each level is an hour or so of gameplay, of course, if you haven't succumbed to one of the many deaths that won't be anything like your fault. Blow the legs off a zombie and it may come back to life as a crawler, nipping at your ankles until you shoot it or kerb-stomp it. Only nine times out of ten, you won't actually be able to see that it's still alive, given that the thing will be the more or less exactly the same colour as the ground. If they hit you once, it wouldn't be so much of a problem as you could step back and take care of the situation, but the game tends to allow them to hit you multiple times quite quickly and if you're already dealing with walking zombies that can seemingly inflict damage without actually coming close to hitting you, you're in trouble. Or how about the suicide bomber zombies, who's piercing screams are nothing but an incredible annoyance? They sprint up on you from a mile away, then detonate when they're stood next to you. Sometimes this explosion will blow you to smithereens even if you're in perfect health and are a fair distance away. At other times, you'll just take a little bit of damage, no matter if you're almost dead anyway and regardless of whether you try to flee or not. In fact, this happens with grenade blasts too. We've been on the second floor of a building, thrown a grenade out of the window and watched it bounce off a wall, and back through the door of the ground floor. Seconds later, the blast which was contained by the room below, inexplicably caused our arms and legs to be cast to the wind. At other times, you can throw a grenade about a zombie's length away from you and not take any damage at all.

In co-op, Zombie Army Trilogy is a lot more fun than in single player. The main reason for this is that you can use actual tactics to get over the ridiculously unfair difficulty spikes that the game throws your way. On your lonesome, you can play for forty minutes without suffering so much as a scratch, before one of the more powerful zombies turns up and destroys you in a second. These more powerful foes are all taken out in the same way, with multiple headshots, and the game seems to give them a strange period of invincibility when you land one. You can hit an enemy square between the eyes, wait for his head to snap back to where it was, take the exact same shot again, and watch as it doesn't affect him in the slightest. Frustrating, to say the least. Also, gone are the ability to take snipers out with lower body shots. If you don't hit them above the ribcage, the game tends to just act as if they haven't been hit at all, which is utterly bizarre. A bullet can pierce their armour and kill them stone dead if it hits them north of their naval, but a shot to the leg (or other delicate area) doesn't even cause them to flinch? Ok, then.

But undoubtedly the worst thing about the overall feel of Zombie Army Trilogy, is the audio design. When you're wandering down corridors, keeping your eyes open for zombie foes that could realistically appear from under the floor, through the walls, or around any corner, you want subtle cues that alert you to where the zombies are. At the very least, you're looking for a bit of survival horror-style tension. Unfortunately, you get neither here. What happens is that when a zombie spawns a kilometre away, you get a blaringly loud wail as if the thing is stood right next to you. So, you naturally spin around to check it out and…well…look like a bit of an idiot as the enemy is outside, four streets over, in the basement of a lead-lined building. On the other hand, when a suicide bomber zombie appears next to you as you're looking down the scope of your weapon, their usual loud and annoyingly constant wailing is reduced to next to nothing, so if you're playing a level where there are a few of these about, you've a 50/50 chance of lifting your head up from your scope and being blown to smithereens. When you've just reached a checkpoint, it isn't so bad. When you've successfully avoided a dozen suicide bombers, taken out an Elite zombie, and just have one shot left to go on a boss, however, it's controller-throwing time.

As we've said, there is fun to be had here. It's just that the fun is more often than not punctuated with more than a fair share of negative points and frustrating oversights.

Conclusion

To say that Zombie Army Trilogy is a bad game would be far too harsh. It does provide bursts of fun and with multiple players, can be a laugh riot, especially in Horde mode. It's just that while it isn't necessarily bad, it just doesn't have the polish to ever push it past that sort of level. Some more variation would have been nice, as would a little bit more care and attention with the overall design. There's no doubt that some will be hooked and will love it – it's certainly therapeutic fare – but with the issues it contains, there's a much greater chance that you'll feel the opposite way.