At first blush, I was a bit skeptical of Whisper Mountain Outbreak’s premise: basically, it’s a co-op roguelike that attempts to translate Resident Evil’s escape room puzzle-solving and survival horror elements into a randomized package. Entering Early Access today, the game is the latest from Indonesian developer/publisher Toge Productions (No Space for the Unbound, Coffee Talk, etc.), and ties in fairly neatly to the recent uptick in co-op horror games, except with an injection of T-virus-tinged zombie blasting.
My hesitance with this core conceit came from the fact that many of the best scares in RE history come from their very deliberate placement; the dog jumping through the window, the first time Papa Baker busts through a wall, etc. The same goes for its puzzles, which, at least in earlier games, have you backtracking through improbably complicated mansions and police stations, looking for the Spades Key, or whatever. It’s ridiculous, but again, the hand-crafted nature of things is often the key ingredient in the best installments in the series, like the 2022 Resident Evil remake and its expectation subverting moments.
However, while Whisper Mountain Outbreak is very much aping the vibe and design of ‘90s era survival horror, interestingly enough, its deep-seated randomness is exactly what makes it such a tense trip through overrun residential neighborhoods and dilapidated school buildings.
The game begins with the player character waking up next to some sort of officer dude, who promptly explains that he’s a member of the Bureau of Research and Investigation of Metaphysics (B.R.I.M.). After sustaining an injury while rescuing you, he expects you to help him find artifacts that can stop an “anomaly” from destroying the world. While there’s a toggle for multiple types of scenarios, for now, there’s only “The Outbreak,” which seems to more or less be a zombie apocalypse. It’s all the barest bones of a story, and really just a pretense to get you out cracking skulls.
As for what this objective entails, after picking a mission from a cork detective board (that looks very reminiscent of one from another co-op horror game, Phasmophobia), you’ll be dropped in one of many 2.5D backdrops that are like an isometric, pixel art-infused version of the kinds of dark alleys and cop HQs that Jill and Leone have blasted their way through countless times. “Winning” a run requires you to beat multiple of these missions.
Each level comes with an objective marked on your map, which, at least in my case, has always consisted of retrieving a briefcase. Of course, locked doors ensure the path to these items isn’t a straight shot, and along the way, you’ll run into puzzles that frequently require a pen and pad. You’ll have to figure out ciphers for safe codes, do math to uncover computer passwords, pick locks, and so on. And you’ll have to do all that while fighting a steady stream of zombies. Beyond this style of puzzle solving, many other survival horror staples are here: ammo is limited, and storage space is even more precious. Mix herbs together to make a more powerful healing agent; you know the drill.
Where things really begin to diverge, though, is how the randomized events lead to dynamic scares. While it’s usually fairly easy to dispatch the smaller groups of zombies, every once in a while, a horde event will happen, sending a mass of hungry flesh-eaters your way—you can take precautions by closing doors and finding a nice choke point, or you can continue towards your objective, dispatching them on the way. On top of this, it seems the longer you take to get through an area, the nastier these groups get, eventually including monsters a whole lot worse than your average walking dead. It creates a tension between opening every last cabinet for extra ammo (which you might want to do because you retain items between missions) and clearing out ASAP.
Perhaps best of all, when you combine the randomness of these monster spawns with the act of puzzle solving, you get some very natural “oh shit” moments. At one point, while figuring out a math problem with a pencil and paper, a zombie crashed through a nearby window, leaving me scrambling for my mouse as I switched from arithmetic to brain-busting. It’s all a bit creepier because these zombies seem to be of the occult, Evil Dead variety, and can’t be cleanly attributed to a rogue pharmaceutical company. Even playing the game alone before release, I could very much see the viral potential of the game’s puzzles meets jump scares, and I say that as a compliment.
When it came to the puzzles by themselves, they offered some solid conundrums, which left me vulnerable, if nothing else. I’m not sure how many unique problems like this the game contains, as these are obviously only effective when you don’t know the answer, but so far, I was impressed by how well this experience translates the Resident Evil series’ puzzle box environments to a roguelike setting.
Another boon is that, while simple, there is a relatively good flow to these scuffles with the undead. By default, you’re equipped with a bat that proves a surprisingly effective tool, especially if you do a charged swing, which knocks foes off their feet and leaves them vulnerable to pummeling. Melee weapons even prove effective against groups, hitting in a wide arc, which lets you stun a whole batch at once. However, the main downside to swinging like a maniac is that this rapidly drains your stamina, something you’ll also need for sprinting and dashing. Running out of juice at the wrong time can be a death sentence, especially if you’re low on rounds.
As for the guns, they’re quite effective at blasting through hordes from range, but are noisy and burn your limited resources. Usually, the key is in combining both melee and firearms, shooting from afar before using your bat to knock back zombies who get within biting distance. And you’ll probably have to put these skills to good use, because after completing a level’s objective, an endless army of monsters will chase you all the way to your car. These moments are effective, tense, and encourage you to have an escape route planned. Although even if you’re prepared, you’ll still have to wait for your absolute jalopy to heat up its engine for 10 seconds before leaving, making a stand-off almost unavoidable.
If I have a problem here, it’s that the game’s UI navigation is perhaps a little bit too faithful to the clunkiness of old school horror games. You can’t quickswap between weapons, meaning you’ll have to click through a menu if your current firearm runs dry—this damn screen has proven more deadly than any brain-eating monsters so far. In a run-based game where biting it three times means you’re done for good, those deaths sting. There are some other clear indicators of the game still being in Early Access as well, like how the English language translations need quite a bit of touching up.
Beyond this, another big test will be if the game’s puzzles and randomized levels hold up in the long run; so far, it’s mostly been “retrieve the briefcase,” but I imagine there will be much more variation as development continues.
Overall, though, I’m largely impressed with Whisper Mountain Outbreak. It smoothly transfers the dwindling ammo and arcane puzzles that survival horror games are known for to a run-based, co-op-friendly structure. While this Early Access launch is already in solid shape, it will be interesting to see what new pixelated horrors mutate from this ground zero.
Whisper Mountain Outbreak was developed and published by Toge Productions. It will be available in Steam Early Access on August 11, 2025.
Elijah Gonzalez is an associate editor for Endless Mode. In addition to playing the latest, he also loves anime, movies, and dreaming of the day he finally gets through all the Like a Dragon games. You can follow him on Bluesky @elijahgonzalez.bsky.social.