If you haven't heard of Beat Saber before, then you're not alone—I only caught wind of it earlier today. But this Early Access VR rhythm game, which is basically a lightsaber version of Guitar Hero, is now the highest rated game on Steam. It's clocked nearly 2,000 reviews with a 99% positive rating, which is enough to put it above everything except the Witcher 3's DLC expansion pass. It's going to change a lot before it leaves Early Access later this year, starting with a major update next week that will let players create custom levels set to their own audio files.

The current version is essentially an arcade mode with a limited number of songs, but it's still got players hooked. The premise is simple: you slash at coloured cubes as they come towards you to the beat, and each one will only be smashed if you hit it from a particular angle. If you want more on the game itself, then Jack interviewed the creator here. 

The level editor will be the same one that the development team at Hyperbolic Magnetism used to create the existing levels, and players will be able to export their own creations and then send them to people they know. It won't have "simple sharing"—which I presume just means you can't upload your tracks for the community to try out—but I'm sure people will start disseminating their own designs via Reddit or forums. 

The main Beat Saber Twitter account today tweeted that we'd find out more information on Friday, but then the game's creator said that it might be ready before that.

You can pick up Beat Saber for $19.99/£15.49 on Steam or the Oculus store.

Once again, Jack's piece is a good place to start if you want to find out more about the game. Watch a short gameplay clip below, and thanks to Road to VR for flagging the Steam rating.

I first saw Hyperbolic Magnetism's Beat Saber on Twitter. Someone retweeted the 30-second video of the VR rhythm game above and I was hooked immediately. 

The idea is that you wield two lightsabers and slash at colored cubes as they zoom toward you. You can't just flail wildly at them, though. Each cube is tied to a particular beat and has an arrow indicating the direction you should strike it from. It's Stars Wars meets Guitar Hero. 

Ján Ilavský, the lead developer on Beat Saber, initially came up with the idea after he bought an HTC Vive and was dissatisfied with the rhythm games on offer. He felt many of them failed to satisfyingly tie the action to the beat, and started to think about how he would go about making one instead.

"I bought the HTC Vive more than a year ago, and I was really looking forward to play some rhythm games, particularly Audioshield," Ilavský elaborates. "I started to play it […] and I didn’t feel the rhythm as much as I was expecting.

"It was fun, but I was looking for something more precise. Where I could feel each note. So I started to think about how to make something similar but to make it feel much more [rhythmic]. The cutting was [the solution we came up with]. So, I made a quick prototype cutting some cubes and we realized it worked really well."

It wasn't always about lightsabers. In an early build, it used standard swords instead. Ilávský changed this, however, after playtests revealed that people were too focused on the angle of their blades and weren't having fun with the rhythm. 

"[The decision] doesn’t actually have anything to do with Star Wars," Ilavský says, perhaps with an eye toward Disney's lawyers. "The first thing we actually had wasn't even a lightsaber. We computed the angle of how high you're holding the saber, but it wasn't good. The obvious choice was to use lightsabers instead, because there's no angle, so you can cut in any direction."

Ilavský is working alongside two other talented individuals: Vladimír Hrinčár, who is responsible for the programming and game design, and the musician Jaroslav Beck. Beck is composing the soundtrack and has worked on a bunch of high-profile projects in the past, scoring music for the Overwatch short films, World of Warcraft, and coincidentally enough the TV spots for Star Wars: The Force Awakens.

The team also aims to incorporate community contributions, with players able to create and share their own levels, and integrate music streaming services like YouTube and Spotify.

Beat Saber looks extremely promising. That initial tweet I saw has blown up significantly, being retweeted over 8,500 times.

"It was a big surprise," Ilavský says, clearly taken aback by how much publicity the short video created for the game. "This was just like, 'Yeah, let's make a small video to remind people we are doing something.' It took me like five minutes to make it. To record the gameplay, to edit it in Final Cut, and to finally release it. And it just happened. [What's funny] is that we were planning to make a huge trailer with actors and stuff." 

Ilavský believes the teaser went viral because of the simplicity of Beat Saber's premise combined with Beck's soundtrack and its escalation. You can immediately tell what you're supposed to do simply by looking at it, but as the clip goes on and music drops it shows that there's a steepening difficulty curve.

The support they’ve received since they released the video has meant a lot to the team. "In March last year, we stopped working on Beat Saber, because we didn’t know how to move forward. We thought like, 'Maybe, this is not the right game to do now.' Then some people asked us to show them the game at some small event. So, we brought the HTC Vive there and like 30 people played the game and they really pushed us to continue working on it.

"It’s really good to hear [the response to the demo]. Usually, when you show a game and it's mediocre or just normal, all your friends tell you, 'Yeah, it's good,' and you're like, 'OK. Maybe.'  But when people say they are going to buy a VR headset just because of your game, then it's different story."

Beat Saber doesn’t have an official release date yet, but both Oculus and HTC Vive support is planned. You can keep track of the development on Twitter and on its website.