Fads come and go, but one fad in particular left gamers worldwide with tonnes of specialized controllers in the shape of musical instruments in their living rooms and most of them are collecting dust. The developers at 24 Caret Games have found a way to encourage people to get those instruments out of the closet and back into action, and like Rock of the Dead before it, Retro/Grade aims to give you a good reason to rock out once again.

In Retro/Grade, you play as Rick Rocket who has just saved the world. However, the problem is that his victory has left a massive anomaly that has reversed the flow of time, so he has to undo each and every one of his actions one by one to stabilize the universe. While Retro/Grade is a side-scrolling shooter, all of the hero's actions have already been decided, so it's your job as the player to ensure he's where he needs to be to undo each and every shot from his cannon as well as avoid incoming enemy blasts, and that's where rhythm comes into play. See, instead of being free-roam, allowing you to go up and down at will, there are anywhere between two to five lanes you must choose between based on the difficulty level chosen, much like in a Rock Band or Guitar Hero game. You don't have to use a guitar, as the game is fully playable with a controller, but it's a great opportunity to whip out those old fake plastic instruments.

When I first saw the trailer, my initial reaction was to assume that my years of playing Rock Band and Guitar Hero would do me well and make even the toughest of the seven difficulties easy, but I was dead wrong. After failing miserably on the final levels (the first ones available to you; remember, everything in this game happens backwards), I had to experiment with the difficulty setting to figure out what worked best for me. If Retro/Grade were just a matter of matching up your location with timed shots, it would be incredibly boring and simple for a seasoned rhythm game veteran, but this is as much a shooter as it is a rhythm game, so avoiding enemy fire and attacks is as important as matching up and hitting your own shots on time.

The additional strategy of avoiding attacks coming from behind really adds a level of depth and uniqueness that makes Retro/Grade stand out from any rhythm game I've ever played, and it keeps the action fresh. While I was quick to dismiss the game as simple and kind of boring for the first couple levels, once I had encountered the first boss fight my opinion completely changed. Not only do you have to avoid a maelstrom of color-coded energy blasts at the same time as matching the electronic beat, but the bosses also swipe at you or shoot laser beams to make the action even more hectic. It would be easy to get lost and confused if not for the color coding; it's still rather chaotic, but in an exciting and visceral way, rather than a frustrating one.

The soundtrack is also great (providing you're into electronic or techno music); you can even buy the original soundtrack for $7.99, or get the game and soundtrack for $14.99. The only problem is that there are only 10 songs in total. Granted, as both a rhythm game and a side-scrolling shooter, Retro/Grade relies heavily on replay value and the ever-present quest for a high score. The campaign is quite short – I finished it in less than an hour – but the game really exposes its longevity when you try the challenge mode, where there's seemingly no end in sight. From the graphic in the background of the challenge map, it's clear that there are potentially hundreds of different unique challenges, so I've only just scratched the surface by completing a couple of dozen or so. Each level is laid out on a branching alphabetized path, and each has its own special prerequisites for winning (such as attaining a specific score multiplier or beating a level under special circumstances). It's still nothing truly new, but it's varied enough to keep you busy for a while.

Retro/Grade is an incredibly unique blend of two genres, which I found myself enjoying the more I played. The gameplay itself is hectic and unique, the music is catchy, and the little snippets of humor spread throughout give the whole ordeal a sense of warmth. While it certainly won't be for everyone, it's a great demonstration of talent and ingenuity, and in a world full of reboots and sequels, isn't that a good thing?