Whenever a major new anime hits the scene, there's a mobile game to accompany it, like clockwork. Many of these games remain Japanese exclusives, with only a handful releasing globally. Additionally, many of these games feel like simple reskins of generic RPG or card-battling content with the usual gacha mechanics to keep fans rolling for their faves. So, when I went into the mobile game based on the MARS RED anime, I was expecting something along these lines. What I got was a pleasant surprise – a full-fledged visual novel/adventure game that acts as a unique side story to the events of the anime series.

The anime MARS RED is about an alternate-history 1923 Tokyo that's dealing with a rise in vampires prowling the city at night. The Japanese government has created an all-vampire sub-unit of the army called Code Zero to deal with vampire-related problems. But there are some vampires who still desire to cling to their humanity, but loathe the idea of joining the military. That's what new vampire Yatsufusa Yuki is dealing with: he doesn't want to become a monster, but he has a deep-seated hate of all things military. Fortunately, he's taken in by Tenman-ya, an oddball outfit that happens to be an employment refuge for vampires. But as a vampire looking to stay on the straight and narrow, Yatsufusa can't avoid crossing paths with Code Zero for too long, and soon he's swept up in their world.

MARS RED presents itself in a visual novel-style format, with small “chapters” each covering a bit of the larger story. Each chapter costs a ticket to read, and tickets are replenished each morning (though you get a bunch to use initially.) The content varies from chapter to chapter: sometimes it's just characters chit-chatting about what's going on in the plot, while other chapters are more interactive, requiring you to “investigate” your surrounding through a simple touch-screen interface and make decisions to deduce what is going on. Depending on how you like to play, this format can be either refreshing or infuriating: you only have limited tickets to use for reading each day before you have to buy more. However, the leisurely-paced story isn't constantly prodding you to spend money on tickets, either. Personally, I liked having a few new chapters each day to read without feeling pressured to spend time or money I didn't want to.

The story of Edge of the Nightmare is a big selling point: it's penned by original series creator Bun-Ō Fujisawa. In other words, it's about as official and canonical as it gets. If you enjoyed the show, the story acts as a nice companion to the events of the anime, and several familiar characters from the Code Zero crew like Takeuchi, Suwa, and Kurusu all play key roles. The game-original protagonist, Yatsufusa, fits in well with the existing cast: he's a bit mopey and confused at first, but it's understandable considering he got turned into a friggin’ vampire. Over the course of the game, we see him grow into his role and learn more about his background, and seeing his character evolve throughout is very satisfying.

The other big feature for fans of the original series are all of the numerous little side stories and episodes scattered throughout. Some chapters in the story require an additional resource in the form of points to unlock, which you earn by sending some of the characters out on exploration expeditions together. These expeditions can take anywhere from thirty minutes to a few hours, and when the characters return, they award you points and loot, but they also grow a bit closer. When their relationship reaches a certain rank, you unlock little “murmur” dialogue sequences where the character will give their thoughts on their various interpersonal relationships.

This sort of world-building fanservice plays into the game's gacha, as well. Rather than characters or upgrades, the primary appeal of MARS RED's gacha is unlocking new side-story sequences featuring the characters. They're completely superfluous to the rest of the game, but they give players an entertaining look at everyday interactions between the cast members. The gacha does offer some in-game items that increase rewards earned during exploration, but the main thrust is on giving you satisfying story content, which I found to be a refreshing change of pace.

As a whole, I found MARS RED's approach to monetization to be very agreeable: much of what you need to play can be earned in-game easily, and you can get more stuff like puzzle hints and extra login bonuses by choosing to have the game run a 30-second ad. I probably could have spent cash on blowing through the story chapters if I wanted to consume the whole thing in a day, but I didn't feel like I was pressured to with any carrot-on-a-stick or unreasonable limited-time mechanics, and that's the important thing.

Presentation wise, MARS RED is excellent: the UI design is intuitive and easy to navigate, resources are easy to find, and the theming of “early 20^th century Tokyo” is clearly conveyed throughout. The illustrations and artwork in general look great, though I was disappointed at how few variations on the character models were in the game: they mostly stand around in the same generic pose with the same expression no matter what is going on in-game. The sound is also a bit of a letdown: There's not much music to speak of, and those looking to hear lots of dialogue from their favorite Japanese voice actors will be annoyed that much of the voicework in the game is simply generic clips.

The English localization is also rather problematic. While it's not completely incomprehensible, spelling errors and noticeable, awkward grammar problems litter the text. Edge of the Nightmare's dialogue could have really used a pass or two through a fluent English editor to really help bring the world and characters to life; as it is now, it's readable but also very dry and a little off-putting when yet another grammar error rears its head.

Overall, I enjoyed playing MARS RED Edge of the Nightmare. The simple visual novel/mystery-adventure gameplay works well in a mobile format that can be consumed in bite-size chunks, and the emphasis on giving players character moments as rewards is a unique approach that I really like. It could use some improvement in several areas, but as a standalone game or a companion to the anime series, it works very well. Fans of the show should definitely give it a look, but even if the anime's still on your to-watch list, there's some fun to be had with the MARS RED game's atmosphere, characters, and crime-solving gameplay.