An ideal mash-up has one foot in desperate plausibility and the other in the whimsical ramblings of an imaginative youth. At an earlier point in my life this was realized through the fusion of candy and breakfast to form Reece's Puffs and it was delicious. The folks at 24 Caret Games apparently spent their nights dreaming of slamming Guitar Hero against a side scrolling shoot 'em up because that's exactly what they ended up making with Retro/Grade. And it's delicious.
Retro/Grade opens at its ending. Rick Rocket saves the day but also creates an anomaly in the space/time continuum that makes time flow in reverse. Subscribing to Timecop's theory of paradox avoidance, you must guide Rick backwards through ten levels and try to replicate every move he previously made. Every single shot Rick fired, enemy that he vanquished, and bullet hell he weaved through must be reproduced in reverse.
A respectable performance in a normal shoot 'em up requires a level of hand-eye coordination somewhere between ordinary genius and Mentat, so the prospect of doing that in backwards sounds nigh impossible. 24 Caret Games solved this potentially brain melting dilemma by pushing Retro/Grade's gameplay closer to Guitar Hero than something like R-Type. Bullets being sucked out of exploding enemies and back into Rick's ship exist on one of three constant lanes across the screen. Each bullet on each lane maintains a color consistent with its place. On mediumcore difficulty, for example, it's green, pink, and yellow from top to bottom (with easier and harder difficulties adding fewer and more lanes, respectively). All Rick needs to do is align his ship with the correct lane and hit the fire button at the appropriate time. Mechanically it's very close to the highways from Guitar Hero, and nailing a shot correctly even builds the soundtrack in a similar manner.
You also need to consider all the bullets Rick had dodged along the way. These fly out of the opposite end of the screen and are attached to the same lanes as Rick's outgoing (incoming?) fire. Moving in and out of various types and patterns of opposing fire while trying to line up shots composes most of Retro/Grade's challenge, but there are plenty of wrinkles along the way. Rick's shots, for example, aren't all missiles. Smaller rockets require a rapid fire button mash for proper absorption, just as Rick's laser gun calls for the fire button to be held down. Rick is a allowed a certain amount of mistakes before he runs out of time, and even those can be corrected through retro/fuel, a familiar mechanic that allows Rick to go back-er, uh forward in time for a couple seconds.
It was through retro/fuel that I really began to appreciate Retro/Grade's commitment to its concept. Your score, for example, gets lower as you play through a level because you're playing a formerly perfect play-through in reverse. Enemies reassembling on screen is expected, but if you pay attention in level 8, Retro/Grade Groove, you'll even notice the night time setting shifting backwards into sun soaked twilight. After completing a level Retro/Grade has the courtesy to offer a replay of the proper level, which adds a great sense of continuity to the whole thing. 24 Caret Games even thought of a way to handle the player starting the game at level 10 by stating "Rick wanted to take care of the most difficult invaders first...All of his subsequent battles were progressively easier," in level 1's description. From beginning to end and back again, Retro/Grade doesn't fault in its mission.
Structurally, though, the campaign felt a bit uneven. For The Win is more or less an entire boss level that employs seldom used mechanics like black holes and introduces a few new challenges exclusive to said boss. The remaining three levels, rather than up the ante, default to throwing old tricks at the player at a slightly more chaotic rate. It wasn't bad, per say, but kind of disappointing and anticlimactic after that devilish boss level.
If Retro/Grade has a significant fault, it's that rhythm fans may get a bit more out of it than more casual players. A respectable six difficulty levels ensures Retro/Grade can be played and enjoyed at any level of skill, but this approach carries varying measures of longevity. Rhythm junkies will fall in love with trying to nab every retro/quark (read: power-up) and avoid all retro/leptons (power-downs) all in pursuit of lower and lower score. Retro/Grade is a game meant to be played and enjoyed over and over rather than a one and done run. Personally I was satisfied with a run on Mediumcore, another on Pro, and a few stabs at X-Treme until I was reminded of my limitations. While I wasn’t able to try it myself, Retro/Grade fully supports (and probably feels better with) a guitar controller, and leader boards even have the courtesy to relay which means of control produced each score.
A lengthy challenge mode helps cover some ground left by the comparatively short campaign length. Ironically I thought this mode was going to be an afterthought but it's actually where I spent the bulk of my time. Branching paths contain lines of challenges, each of which putting a particular spin on a level from the campaign. There's actually a wide variety of challenges, including zooming the camera super close to the player, re-coloring your lanes, adding crazy disco lighting, and playing a level at different speeds. Every so often there's a prize to be unlocked on the path, and those include some extremely cool ship avatars, various cheats, and the usual suspects like music and concept art. There are even warps should you want to go directly to the harder challenges. The leader board for challenges also appears to be a cumulative total of your score from every challenge (at which I'm currently ranked #1, woohoo), which is a bit different and more economical than a hundred different leader boards for each challenge.
I'm sort of ashamed to be this deep in the review without bringing it up yet, but Retro/Grade's soundtrack is fantastic. Music is always going to be the most crucial component of a rhythm game, and Retro/Grade's infections electronic suite hits all the right notes. You're obviously going to get more mileage out of the soundtrack if you're playing on higher difficulties and "making" more of the notes, but it remains catchy through any method of absorption. With its bright neon colors, surprisingly detailed backgrounds, and playful aesthetic, Retro/Grade also looks better than a $10 game should. I do wish I had more time to observe and appreciate the activity in those backgrounds, but I didn’t want to risk taking my eye off the ball.