
An impossible locked-room murder: Captain Mortuga lies dead beside an ancient cauldron aboard the world’s strangest submarine, crewed by sketchy suspects. A handcrafted point-and-click with sharp humour and tricky puzzles. Dive into the next mystery from the creators of Tangle Tower & Crow Country.
Modeled estimate, not a reported figure. How we estimate →
Media

About
In the pitch-black waters beyond a long-abandoned fishing town, the enigmatic captain of the world's strangest submarine has been murdered. Some say he was an immortal time-traveller. Others say he was a vampire, cursed to stay hidden beneath the waves forever...
Found alone in a locked room, with only an ancient stone cauldron to suggest how he might have died, it's up to Detective Grimoire and Sally to piece together what really happened. Was it a curse, released from the cauldron? One of the submarine's eccentric crew? Or does the bizarre truth run even deeper...
• Every clue is a fully realised 3D object waiting to be examined for hidden secrets
• Grimoire and Sally are back, and joined by a fully voiced cast of mysterious suspects
• A hauntingly beautiful original soundtrack performed by the Budapest Art Orchestra
• Explore every hand-painted inch of The Mortuga Submarine, where not all is as it seems...
*Voice audio is only in English
Stats
All-time low is the lowest price we've recorded for this game since we started tracking it.
Languages: English*, French, Italian, German, Spanish - Spain, Japanese, Korean, Portuguese - Brazil, Russian, Simplified Chinese, Spanish - Latin America, Traditional Chinese*languages with full audio support
Engagement
Hours played at review time, across 200 reviews with recorded playtime.
Reviews
Themes across 200 recent reviews and how positive each mention is. A keyword signal, not full sentiment analysis.
positive critical· bar length = how often the theme comes up
Reviews
An excellent follow-up to Tangle Tower. The mystery is engaging, and the developers trust you to tackle the mystery at your own pace and at your own direction. Puzzles are fun head-scratchers, I definitely needed hints here and there. (Also, you can play with zero hints, which I did until I would cave on the occasional puzzle I couldn't wrap my head around!) The real heart of the game is the unique oddball characters. Beautiful animation and fantastic voice acting for every character in the game. I love that the devs included a gallery with all of the concept art and various notes about the game's development. The series continues to be a gem. SFB will continue to be an instant buy for me!
One of the best Detective stories I've experienced.
Her.
Masterfully designed, such a great game with very intricate storytelling.
This game is everything I hoped it would be and more. I can not emphasize enough how fun it was to discover the motivations of some characters and the killer. I was and still am enthralled by the game and its characters and story. This game was so well crafted, so charming, funny, and gripping. The wait has been more than worth while.
What a marvelous story, grabbed the heart out of my chest. This was worth the long wait. Gameplay is fun, the jokes are witty and i found myself cackling at some of the gags. Such an experience.
An incredible sequel to an already incredible game. It's fresh while still connecting tothe previous titles in a believable way. Absolutely worth the years spent in suspense over the details of it's release
So I opened this game, blinked, and 7 hours had passed. I don't think I've ever willingly done something for 7 hours straight without a break. And I'm only 50% of the way done with the game! This thing is incredibly charming- I find myself asking every single character about every item even if it's not relevant just to enjoy the dialogue. The animations and design are so beautiful, and I really appreciate the care put into each story. Can't wait to finish it! Definitely a worthy successor to tangle tower! I'm absolutely loving it so far
I played this game as soon as I physically could and I have to say... Absolutely worth it! This is the perfect follow-up to "Tangle Tower". The story manages to be self-contained while also referring back to the previous games, making it a satisfying experience whether or not you've played "Secret of the Swamp" and "Tangle Tower"
So worth the wait! This game is INCREDIBLE! I love all of the Detective Grimoire games, and this one had me hooked right from the start. I love how unique the puzzles are and how I felt so accomplished after solving them. 10/10 amazing amazing game!
Related
Related
Trends
Steam followers (game-group members) tracked daily from when we started recording.
Momentum
Pace estimated from the game's recent review growth (our daily snapshots) at its own sales-per-review ratio — a momentum signal, not booked sales.
Audience
Audience
Games most often reviewed by the same players — an audience-affinity signal from our review sample, not full ownership data.
Estimated from the language of this game's reviews — a proxy for where players are, not official Steam demographics.
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