Onechanbara is a combination of two Japanese words: one-chan means elder sister, and chanbara is effectively the term for Japanese sword-fighting samurai films. The result of this combination is a surprisingly long-running series about bikini-clad samurai sisters brutalizing undead monsters. Onechanbara Z2: Chaos is the latest title in the franchise, and it's the first one for next-generation systems. If you want to see scantily clad women tearing a bloody swath through foul zombies, you've found your game. Unfortunately, the same dedication to that concept can also feel like a lack of ambition.

Z2 opens in medias res. Kagura and Saaya, two vampiric zombie hunters, are facing Aya and Saki, rival monster hunters. Before they can fight, they are ambushed by a robed woman who sends them tumbling into the depths of the underground, where the four hunters are forced to work together to survive. After they escape, they find out that undead monsters have begun attacking across the globe. Now the four must team up to kill zombies and find the woman who attacked them before the world becomes an undead paradise.

The plot in Z2 basically amounts to "kill a bunch of zombies in various locales." Fortunately, it's held together by a top-notch translation by XSEED. The characters are absurd, but the dialogue is frequently funny and utterly shameless. The characters being angry, loud and foulmouthed fits the tone of the game better than something more subdued and subtle. It isn't quite as excellent a translation as Akiba's Trip, which carried the game almost by itself, but it adds a lot of much-needed flavor to what is otherwise a rather repetitive journey.

There are a lot of games about killing zombies, but Onechanbara is entirely about that. The game throws you into large, linear stages packed to the brim with the undead and gives you access to katanas and chainsaws so you can tear through them like butter. You have light attacks, heavy attacks and a subweapon (e.g., throwing blade, heavy mace), and you're facing a whole lot of zombies. You can chain together attacks in a variety of ways, all of which are terrible for zombies. You're able to both dash and dodge, which allows you to remain almost constantly on the offensive. If you're not attacking at any point in Z2, you're probably doing it wrong.

Gameplay-wise, you have four characters: Aya, Kagura, Saaya and Saki. Each character plays extremely differently, although Kagura and Saaya are from a vampiric clan that can absorb blood and recover health while Aya and Saki are trained in special techniques to slay evil. The result is that Kagura and Saaya tend to be about unrelenting offense while Aya and Saki have more finesse. For example, Kagura can afford to take hits since she can recover health, while Aya can instantly kill Mudmen but needs time to set up. Both she and her sister have a special slow-motion dodge that allows them to counterattack if they perform it at the right moment.

All four characters are present in combat at once. You control one of the four, but at any time, you can swap to another one. By doing this mid-combo, you can unleash special attacks. Constantly swapping between characters offers a lot of flexibility, so you can keep combo chains going way longer than with a single character. If you're patient enough, you can tap the touchpad button once they've charged up and get up to three AI allies battling alongside you. Each is more than capable of handling the usual minions on their own. This doesn't prevent you from swapping between them, so it lets you turn the group into a buzzsaw of death.

Speaking of which, Z2 also retains the trademark Stain system, which is sort of a super mode. As your characters fight, they're covered in blood, and when they are stained enough, they go into a berserker mode where all damage and abilities are amplified. After a certain point, Transformation is also an option, so Kagura and Saaya can turn into demonic forms to further increase their combat abilities — though it also causes their HP to drop rapidly. The Stain meter gradually depletes, and once it wears out, you're back to the regular vampire cowboy samurai killing sprees. You can lessen the depletion by swapping characters, allowing you to save high-damage super modes for bosses and difficult foes.

Z2 is one of those games that presents a lot of mechanics in an attempt to imply extreme depth. At the end of the day, you can succeed and even achieve the coveted V ranking by simply smashing the Square button and occasionally canceling your moves. The game loves to throw character-specific moves and concepts and abilities at you, but most of them are pretty useless. The wear system feels like a waste of time. As you fight, your weapon becomes covered with blood, and you have to tap a button to clean it or else you do less damage. It's so easy to remove blood from your weapon mid-combo that the only reason it would even be an issue is if you forget that it exists.

The game has some difficult moments, but unfortunately, they're difficult for the wrong reasons. You can adjust the camera somewhat in the menu, but it loves looking in the wrong direction and has trouble keeping up with the fast movement of the characters. That isn't bad during regular fights but can be annoying in boss fights. On more than one occasion, the camera was trapped inside the boss despite my best efforts. A lot of action games do everything they can to make sure you've got a clear idea of what is going on, but Z2 isn't great at that. Regular enemies tend to fade into the environment, so fights can last longer than they should as you run around looking for a single zombie who is stuck in a fence that's almost the same color. Bosses are better, but smaller foes tend to be overwhelmed by the visual effects, which make it harder to notice their attack animations. This varies from level to level, and some are better than others, but the game mostly feels like it is more style than substance.

The boss battles are somewhat of a highlight in that they feel like the most distinctive part of the experience. Bosses are large and gross and require you to tear them limb from limb to defeat them. This is done largely by beating them up, followed by QTE events using the PS4's touch pad. The latter bit is surprisingly well integrated, and I never missed an input. The biggest problem with boss fights is that they're just as button-mashy as the rest of the game. I would save my Stain meter for them, use it, and watch most of their health vanish in a handful of attacks. There are a couple of standouts, but the boss battles are more about the spectacle of the QTE events than the actual fight.

Z2 is reasonably fun, like Dynasty Warriors and its ilk. It's fun to tear through lots of zombies in slow motion with a variety of weapons. The major problem is that there's just not a lot to do. Once you've gotten through a few stages of the game, you've seen the majority of what it has to offer. The quips and occasionally interesting boss fights liven things up, but the combat lacks a sense of progression. The game remains fun as long as you enjoy watching violent, loudmouthed, bikini-clad samurais killing zombies. The second that wears off, you're going to be tired of the game.

There's a bit of unlockable content, but the bulk of it revolves around new costumes for your characters. There are a lot of customization choices, as you can find a variety of accessories and costumes. As befitting of the game, the majority are swimsuits that range from relatively modest to basically naked. This is not a game to play in front of grandma. There are higher difficulty level options available, but they don't do much to make the gameplay more fun. By the time you reach the end of the game's 16 levels, you probably won't be very interested in the challenge-based Mission mode that tasks you with slaying even more zombies under special circumstances.

Z2 is a budget title, and it shows. The visuals would be quite bad for a PS3 game, never mind a PS4 one. The character modes are simplistic, and the animations are reasonably smooth. Far more significant is that the environments and enemies look bad. The game runs at a fairly smooth frame rate, which is welcome considering the amount of splatter on-screen, but the game is one of the poorer-looking games on the PS4. The soundtrack is excellent and features a lot of catchy tunes that make it quite fun to slaughter your way through hordes of the undead. The voice acting is also surprisingly good, with the ridiculous script being saved by some quality line-readings and a solid translation.

Onechanbara Z2: Chaos promises two things: fan service and zombie killing. It delivers on that but not much else. XSEED's lively translation and the sheer fun of zombie killing make it an enjoyable enough romp, but low production values and repetitive gameplay really drag it down. It's difficult to fault a game for wearing its heart on its sleeve, but it feels like more time was spent on skimpy costumes than level design. It's slightly cheaper than most games but not cheap enough to be an impulse buy. You'll get plenty of what Onechanbara offers, but don't expect much else.

Score: 6.5/10