Killing Floor 2 is the sequel to Killing Floor (shocking, we know), a four player co-op, zombie survival game whose closest comparison and competition is the Left 4 Dead series.

This game not only brings over the core concepts of shooting brainless monsters with friends, but also a strange release schedule.

The original Killing Floor was a mod for  Unreal Tournament 2004 that originally launched in 2005. A retail release, however, didn’t arrive until 2009. Killing Floor 2, on the other hand, first saw the light of day back in April of 2015 in Steam’s Early Access programme.

Jump to November 18th, 2016, and the game has left the comfort zone of Early Access to general release. So how does it fair in the wild?

Killing Floor 2 review: First contact

Your first hour or so with the game will leave you feeling lost and confused. While the tutorial does a good job of teaching what you should be doing with your hands, it leaves you blind on many other aspects.

How do you find a game? Which mode and difficulty should you choose? How do you equip weapons and perks? There’s nothing to really guide you and you just need to be lost for about half an hour before you jump into a game and see what’s what.

Because Killing Floor 2 is a co-op focused title, you’ll need to surf through a massive list of servers to find a game to join. If you’re partnered with a friend (or friends), or feel brave enough to play alone, you can create your own game instead of joining another.

Once you’re in a match things are a bit simpler. You have a gun, you shoot zombies. It’s that simple. Killing Floor 2’s shooting mechanics work fine, but there’s nothing special about them. The biggest complaint we have about them is a lack of punch. We spent the most time with the Support class who specialises in shotguns, and even the automatic one with a huge drum clip felt like a Nerf Blaster.

There are grenades and melee weapons to shake things up, as well as a bullet time mechanic. “Zed Time” will activate randomly in instances such as multi-kills or impressive headshots.

Honestly this mechanic is irritating at best. If any player on the server activates Zed Time the entire game will slow down. Your shooting and movement slows to the same degree, so you only get a marginal benefit from the mechanic at best.

The targets on the other side of your gun – called Zeds or Specimens here – are much more interesting and may be the best part of the game. The people who designed and animated the Zeds at developer Tripwire Interactive deserve a raise. Every Zed, even the low level grunts, move in a legitimately creepy way that manages to look natural and superbly unnatural at the same time. Killing Floor 2 isn’t supposed to be a horror game – your teammate tea-bagging corpses and the awesome metal soundtrack would never allow it – but the Zeds on their own are plenty scary.

Killing Floor 2 review: Getting the hang of things

Each match of Killing Floor 2  plays out the same way: defeat a wave of enemies and a store will open allowing you to spend earned currency on upgrades. Rinse and repeat until the waves finish and fight a boss.

But, after you’ve done this a few times, that sense of confusion will kick in again. We really did think we were playing the game incorrectly for our first couple of hours. The upgrade store, while simple to manage, doesn’t really let on what’s the best way to spend your money. There’s an autobuy option which puts in the leg work for you, but it feels like it makes strange decisions on your part.

What’s more, it leads you to this game’s biggest problem: how it handles leveling and progression.

Each of the 10 different classes in this game can be leveled up to level 25. Every five levels you obtain access to a new skill which drastically improves the character.

That sounds great, until we found out how much grind this takes. Five hours of play netted us five levels in Killing Floor 2. Before we could reach the exciting skill of either having larger magazines or a faster reload, we had to invest five damn hours.

Sure, this can be sped up by playing harder difficulties with bigger parties,and the tutorial is kind enough to instantly take you from level zero to one, but that is an unnecessary amount of grind. It’s the kind of disregard for your time that you expect to experience in a free to play game, not something you have to pay for at the door.

Killing Floor 2 review: High level stats

We soldiered on with this game, still thinking we were playing incorrectly. To help us we started to join servers with more experienced players. One such server showed us what it takes to be successful in this game. Two local players (on a local server too, which was a nice surprise) were levels 25 and 19 respectively and basically had the game nailed down to a science.

They knew exactly where to stand on the map, had the locations of the upgrade stores memorised, and the enemies just weren’t a challenge for them. And you know what? They didn’t look like they were having a lot of fun.

As we leveled and more of this game opened up to us, we found out that there’s nothing to look forward to in the end game. We asked around on the Killing Floor 2 subreddit and our suspisions of seeing everything the game has to offer in the first hour were confirmed.

When you reach this point in Killing Floor 2 you have two choices: continue the grind to try and eek out levels to see the later skills, or stop playing. We were in the latter category, until we found one mode of the game we had been missing.

Versus Survival (this game’s only other mode) is what stopped us raking this game over the coals for a lack of content. In this mode, the players are split into two teams. One team fights normally as human with guns in first person, while the other team controls the hordes of Zeds trying to kill them.

Each player on the Zed team controls a single specimen and has access to all their abilities. All the cool animations and designs of the Zeds really shine when you get to control them and provide a much needed change in gameplay. If the humans can survive all the waves, or they all die, the sides switch.

After grinding in the regular Survival mode, this was a godsend. We really do think that this is the way to play the game, and it was a lot more fun than the vanilla mode.

Killing Floor 2 review: Verdict

We skipped over many other annoyances we had in this game. Some of the Zeds have really cheap mechanics, for example. Who doesn’t like trying to survive in a game that has invisible monsters? We know we do!

But the biggest problem that we haven’t mentioned yet is the in-game store. This aesthetic-only economy is extremely similar to the one in Counter Strike: Global Offensive. Playing unlocks chests which can only be opened with keys, and they can both be bought with real money.

While we believe that a cosmetic-only store is miles ahead of selling objects which make a difference in the game, we can’t help but feel like it shouldn’t be there. CS:GO can stand on its own two feet and be an addictive, captivating game on its own, and Killing Floor 2 can’t.

And that’s the conclusion we have on this game. It’s just missing too much to make us want to fire it up again. It’s miles better playing with friends, but we can’t in good conscience recommend it.

There’s been a surge in co-op focused games in recent years, and Steam is absolutely full of choice titles that are better than this game. We think we can only recommend Killing Floor 2 to PlayStation 4 players who don’t have access to that library.

• Killing Floor 2 was reviewed on PC. A review copy was provided by the publisher.