Zombies have been the perennial whipping boys of the shooter genre for a while now, and it was inevitable that at some point they'd get mashed up with Nazis – second in the cannon fodder league table – to create the ultimate guilt-free targets to blast away at. While Zombie Army Trilogy on the PlayStation 4 is far from the first to wheel out these undead fascists, it does attempt to bring a unique spin to the battles against its undead legion, by employing many of the mechanics from the Sniper Elite games – including its infamous kill-cam.

This release is actually a re-mastering of two pieces of PC exclusive content, with the addition of a brand new third campaign chapter to round out the trilogy. The setup is simple: World War II is coming to a close, and Hitler's trapped in his bunker as the Allied Forces assault Berlin. Not being someone who gives up easily, the most hated man in history has one last trick up his sleeve, and that's to raise an undead army, through which the Third Reich can "live" on.

In the game's campaign – which can be played solo or with up to three other players in online co-op – your band of snipers will travel across Berlin and the surrounding area, locating occult artifacts in order to stop this undead army from sweeping across Europe. Most story chapters all play very much the same, with you or your group following a linear path through a selection of war torn locales, taking out the undead as you go, and resupplying your weapons in each safe room that you reach.

Graphically, the release certainly looks like a re-mastering of a game from the previous generation, but on the upside this means that it manages to maintain a smooth and steady framerate throughout – even when you're facing a sea of zombies and throwing grenades all over the place. While it won't be winning any beauty contests, this spin off does carry the Sniper Elite torch well, gratuitously rendering the damage that you're doing to your targets, with heads popping, bones splintering, and limbs flying.

The kill-cam – a hallmark of the series – also returns. This means that each time that you pull off a decent sniper shot, a camera follows the bullet on its trajectory in glorious slow motion. This also gives you an x-ray view of your target, enabling the game to show every shattered bone and ruptured organ as your bullet tears through each zombie. There's still something immensely satisfying about this relatively minor reward, and even if you've played numerous hours of the Sniper Elite games in the past, you'll be happy that it's made a return here.

The trouble is that since Zombie Army Trilogy is a more co-op focussed experience, the kill-cam has to be dialled back significantly when playing online with others. Since you can't freeze time for everyone when a replay's triggered, you're instead treated to a higher speed version that has no x-ray view. This is such a far cry from those that you see when playing solo that you can't help but feel that it might have been better to remove these replays entirely, rather than including a horribly hamstrung version.

While there is some fun to be had messing with the kill-cam while playing solo, the occasional high difficulty spikes – and the fact that there's no-one to revive you should you get killed – will lead to frustration kicking in all too quickly if you go it alone. Dying at the same point numerous times and facing the prospect of battling the same mass of enemies again will quickly lead you to the conclusion that the only way to play this title is with others.

It's lucky, then, that standing shoulder- to-shoulder with your co-op fire team and sniping a crowd of Nazis as they shamble down the street towards you is really fun. What's more, since there aren't any character classes, everyone's role is simple: kill as many zombies as possible, as fast as possible. This makes playing with random players online a much less frustrating prospect, and while there'll still be the occasional idiot who won't stick with the group and will manage to get killed over and over, this won't tarnish the experience too much.

In addition, there's a variety of difficulty levels, which allows you to tailor the experience to the right skill level for your group, with the highest difficulty – Sniper Elite – requiring a much greater level of coordination to succeed for even for the most capable of zombie head poppers. You can also scale the size of the undead horde to suit your tastes, allowing masochists out there to take on enemy numbers designed for four people all on their own.

You may be thinking that in the zombie apocalypse a sniper rifle wouldn't be first on your list of must-have weapons, and while you do also have access to a pistol and secondary weapon – like a shotgun or submachine gun – in the case of the Zombie Army Trilogy, successful long-range head shots are key. This is because failing to destroy the brain will lead to previously dead zombies resurrecting to continue their attack, and while the explosives such as land mines, trip wires, and grenades help with taking out crowds of the undead without this worry, the sniper rifle will end up being your go-to gun.

This leads to one of the fundamental problems with the game. As Sniper Elite's stealth gameplay wouldn't really work in a brainless zombie context, every encounter ends up as a straight-up fight where you try and avoid getting overrun by the advancing enemies. Developer Rebellion mix things up a bit with the introduction of some different enemy types, such as sniper zombies who shoot back or super elites who wield machine guns or chainsaws, but it all ultimately boils down to you scoring head shots.

And no matter how much fun it is to shoot zombies in the head, by the time that you've done it for the 1,000th time, you'll begin to wish that there was a bit more to experience. The inclusion of a combo system with score tracking – which encourages you to chain together kills without missing a shot – adds a bit of competition, with each player vying to prove that they are the best shot. However, with no reward for coming first, this turns out to be a pretty hollow inclusion.

If you do fancy a break from the campaign missions, there's also a horde mode available where you and your squad mates will face increasingly tougher waves of enemies on a variety of smaller maps. While from a gameplay perspective this doesn't offer much of a difference from the rest of the game, there's at least more of an opportunity to use explosives to help you to avoid getting flanked – or to cover the various choke points on the map. It can be satisfying to set up a series of traps guaranteed to bring a swift death to anything shambling into the area, but in no time at all, you'll be back on the headshot treadmill.

Conclusion

Zombie Army Trilogy is an enjoyable co-operative shooter that's a lot of fun when played with others. Unfortunately, it runs out of steam all too quickly, giving you a severe dose of déjà-vu once you realise that you're playing very similar encounters, with only the backdrop changing. As a result, you'll have had enough of shooting zombies in the noggin well before you reach the end of its campaign, and while you'll look back fondly on the early hours that you spent with this title, you'll wonder if it was really worth bringing it back from the dead on the PS4.