2020 has been a good year for video games, and few are as original and frankly strange as Vanillaware’s Thirteen Sentinels: Aegis Rim. A sweeping anime epic and quasi-real-time tactical experience, it defies easy categorization but nevertheless leaves a strong impression.

The clear star of this title is its story, a tale of thirteen Japanese teenagers who find themselves riding into battle within giant mechs against towering robotic kaiju. It is a piece of mech fiction that recalls Neon Genesis Evangelion, but it very rapidly reveals itself to be a complex pastiche of genres and influences, not all of which I am comfortable listing here because the mere mention of them would constitute spoilers. And yet despite so many homages and references it holds, Thirteen Sentinels manages to feel like its own unique story.

However, it is quite complicated. You’ll realize within the first ten minutes or so that it involves a lot of time travel. You’ll then discover that the narrative is broken down into different sub-plots, one for each protagonist. Once you get past the opening hours, you’ll have the freedom to decide which character you want to play at any given time. As you play, more characters unlock until you have access to all thirteen protagonists. These stories are not presented in chronological order, and you’ll need to rely on context clues to understand how they exist in relation to one another. Some characters’ stories take place very early in the overall narrative, some very late, and one exists almost entirely within a single moment in time. It’s a lot to keep track of. Did I mention that there’s time travel?

Which is not to say that the game expects you to keep up with its many twists and turns without assistance. An entire section of the game is simply titled “Analysis,” and is divided into two sub-areas: Mystery Files and Events. Mystery Files are an encyclopedia of characters and terminology that unlock as you play, either automatically at specific points or upon spending a Mystery Point earned in combat. The entries update automatically as you progress, and they are quite thorough, going well beyond merely summarizing plot-important information; if there is a Japanese term or nickname that you don’t understand, odds are good it is explained here. Meanwhile, the Events section is a timeline of all the scenes in the game, further broken down based on protagonist story and which time period the scene takes place in.

Progressing through the complicated story is shockingly engaging. Scenes never last more than about ten minutes or so, and you’ll simply be navigating them as a sidescrolling adventure game. Rather than picking up items to combine for puzzles, you’ll encounter terms which are stored in the character’s thought cloud. These terms can be considered on their own either to just learn a little more or to progress forward, and they may need to be “used” on a character to trigger important dialogue. Many scenes branch, and multiple days of time are frequently represented by revisiting scenes and exploring alternate routes. For example, an early scene in Iori Fuyusaka’s story has her deciding which snack to eat after school. Selecting crepes will take you down one narrative path, and on a return trip selecting hot dogs will take you down another. It’s a very simple system rendered rather easy by the fact that you can pull up a flowchart of the scene at any time to see what you have and haven’t explored, but the story is so full of hooks that it keeps things moving at an addictive pace, somewhere between the dramatic reveals of a soap opera and the endless mysteries of a J.J. Abrams-style puzzlebox.

None of this would work without a compelling story, and it works better than it should. Each protagonist has their own personality and conflicts, and they don’t overlap as much as you might expect. Juro Kurabe is a bit of a nerd who loves kaiju movies, but is haunted by dreams where his name is Juro Izumi, a dashing mech pilot and mass murderer. Takatoshi Hijiyama is a young man from 1945 who struggles to understand his attraction to another young man while wanting to use time travel to change the course of WWII and also has an unhealthy fixation on yakisoba pan. Yuki Takamiya is a tough gang leader who finds herself tracking down a missing friend while unraveling a government conspiracy. Every story is unique, and deeply weird, and populated with well-voiced, likeable characters. And all of this is paired with Vanillaware’s signature gorgeous 2D artwork, which lends a painterly air that elevates the proceedings.

Unfortunately, the compelling sci-fi melodrama that unfolds is married to a much less interesting combat mode. Combat sees you taking a team of up to six protagonists out into the city to fend of waves of kaiju, with the rest composing an uncontrollable defensive team. Each wave is its own level, and each level is in fact one part of a single massive battle that takes place at the chronological end of the narrative. Battles use a quasi-real-time system similar to the Active Turn Battle system from Final Fantasy. Characters can move, perform an action, defend, or repair their mechs when it is their turn. Once they do any of those things, there is a brief cooldown before they can act again. There are four different classes of mechs, each of which has different capabilities, and each protagonist levels up to learn unique passive abilities. Defeating kaiju and clearing levels earns you currency to upgrade your team, while bonus objectives allow you to earn Mystery Points for the Analysis mode. While six characters can be deployed at once, they have to manage their brain load; after two missions, they have to cool down, participating in neither the offensive nor defensive team until the next mission. Each mission is simply about surviving the kaiju assault until city defenses activate, or wiping out all the kaiju, and it never takes more than ten or fifteen minutes to complete. It’s zippy and filled with ways to customize and upgrade your team. It also looks like this:

And therein lies the problem. The story mode of Thirteen Sentinels is vibrant and personal, with lush art and numerous twists and turns. The battle mode is abstract and sterile, with mountainous mechs and monsters reduced to blips on a wireframe map, and there’s painfully little variety across the 30-odd maps that make up the core of the mode. Terrain is of little consequence and there are a limited number of kaiju types. While the mode is mostly turn-based, it moves so fast and it’s so busy that it’s hard to really strategize or even follow exactly what’s going on. The whole thing is just strange, sapping the vitality and excitement from the premise. It’s not bad; I’d say it even has a lot of fundamentally good ideas. It simply pales in comparison to the narrative side of the package, and is a chore to play. I’d love to hear a post-mortem on what took them down this inexplicable path.

Unfortunately, you can’t ignore the combat. There will be times when you cannot progress through a character’s story until you reach a specific milestone in the combat mode, and vice versa. The ideal way to play is to alternate, playing one ten minute-ish story segment and then one ten minute-ish battle, allowing you to progress without ever having to slog through a big chunk of levels, but the fact is that it never stopped being a chore. Fortunately, you can adjust the difficulty of the battles at any time, and the game in no way punishes or rewards you for your choice. I tried my best to engage with it on Normal, but ultimately dropped things down to Casual so that it didn’t present much of a block to my progression.

Beyond the generally meh combat, the game does suffer from Vanillaware’s trademark horniness. I was willing to cut them some slack for Dragon’s Crown given that it was a pretty tongue-in-cheek exaggeration of pulp fantasy art, but Thirteen Sentinels doesn’t really have an excuse. Morimura is almost grotesque, and the teens are all rendered naked whenever they enter their mechs. There’s actually a plot-specific reason for it, but somehow I don’t think the plot required that most of the female characters get just a little butt curve in their portraits while the male characters aren’t visible below the chest. It’s far from the worst thing I’ve ever seen in an anime, but it did make me roll my eyes, and if you’re sensitive to that you should be aware.

There is also a queer relationship in the game between two male characters that’s handled…pretty well? It initially seems like it’s just going to be sort of fetishistic, but by the end I thought they had the most realistically complex dynamic, and the horniness looped around to being sex-positive. I’d be curious to hear others’ thoughts on it, though.

Thirteen Sentinels is a deeply strange game. If it was just the combat mode, I’d say you should give it a hard pass. But the story is so fun and engaging that it carried me through all 30-odd hours of playtime. I liked it so much I platinumed it, even though that meant spending a little extra time with the deeply mediocre combat. It’s one of the best games I’ve played this year. I’m not sure I’d call it Vanillaware’s best game, simply because Odin Sphere: Leiftreiser better integrates its combat and story in such a way that I’m not actively bummed out about having to play it, but Thirteen Sentinel’s dizzying ambition and heartfelt storytelling elevate it above its flaws. An easy recommendation for anyone who has any interest in sci-fi anime.