Stone Castle Invictus Settlement in Synthacrosia | World Anvil

Stone Castle Invictus

The Industrious Castle City of the Fifth Floor

Broken. Every single soul within is Broken. Do not enter, lest ye want to become broken as well; avoid the castle, avoid the clockwork, and avoid the sound of ringing metal.
— Warning sign posted on the foothills surrounding the Castle
Great dark gray stone walls stand towering over the expansive landscape of The Daybreaks mountain range. Twelve different towers stretch upwards, connected by thick walls. A massive keep stands in the center of it all -- it's windows are dark, occupants unseen, and yet dark smoke continuously rises from the hidden machinery within. Resident's of Synthacrosia's Fifth Floor avoid the castle, for what once was a place of peace is now overrun by automatons with malicious intent.  


The majority of space on the Fifth Floor is taken up by a massive mountain range known as The Daybreaks. Nestled within and upon these mountains is the daunting castle known as Stone Castle Invictus. Its walls, towers, and supports are made of a rough hewn, dark gray stone, and is unnaturally cold to the touch. Above it stretches The Great Tree, it's massive branches filtering out the endless daylight of the fifth floor.  


The Seperatist Wars, also known as the War of the Fracture, broke the Fifth Floor. Physically, the floor underwent massive changes. The ceiling of the floor, which previously emulated a regular day and night cycle, froze. The floor was trapped in endless daylight. The slopes of the Daybreak Mountains crumbled, revealing the dark, twisting, abyssal network of caves known as The Down Deep.   Metaphysically, the flow of time was entirely altered within the floor. From The Floor of Study's point of view, it has been 500 years since the Separatist wars. The Fifth Floor has instead felt twice as many years go by; the passage of time within the floor increasing to double time.   While the other floors of the tower continued life as normal, the Fifth Floor suffered in it's broken state, festering like a quarantined wound. Cut off from the other Floors, the broken could do nothing but wait.


The breaking of Floor 5 broke the denizens as well. Memories fled, reasoning abandoned them, and tribalism occurred. After a short bought of infighting, the majority of the souls left Castle Invictus. They were forced out by the clash of ideals, and clash of flesh vs metal. A small minority of souls chose to side with the newly corrupted clockwork as they took over the castle, while the rest hid in the trees.   The minority of souls remaining in Castle Invictus had allied with the corrupted clockwork responsible for the War. Whether suffering from Broken Core, or just evil at heart, the remaining souls began to worship the clockwork. These two groups, the Broken Souls and the Clockwork, ruled over Castle Invictus together, though haphazardly. It took many years before they appeared to be working towards a single unified goal. Eventually though, the sound of ringing metal and sight of rising smoke signified their cooperation.

Throne Room.png


The Castle, Unified

Somewhere around 200 years into the Fifth Floor's thousand year curse, the Stone Castle began it's work. Black smoke began to pour from various towers and spires of the Castle. Piles of chaff, stone, and debris began to grow outside the walls on the slopes of the mountain, as tunnels were dug deep. The Clockwork and Broken Souls of the Castle had begun work on Synthacrosia's second Clockwork Forge.  

The Self Replicating Machine

Nearly 300 years after construction began, the second Clockwork Forge was finished; it's location known only to residents of the Castle. Immediately upon completion, the forge began pumping out more and more clockwork soldiers, adding to the horde. Stone Castle Invictus had it's focus change from building the forge, to continuously supplying it with materials.   An endless stream of autonomous brass began to filter through the tunnels dug below the castle. Each one was an exact copy of the next. The numbers of clockwork automatons soared, soon reaching the thousands. For the most part, the clockwork seemed singular in their motivations; they ignored the Great Tree, and those who resided within. The newly created clockwork filled the corridors of the Castle, where they remain to this day.   Finally a point was reached where it appeared the clockwork horde could increase no more. The smoke still rose from Castle Invictus, signaling that the industry within was still going strong. However, whatever was being built could no longer be observed from outside.
Wes hasn't seen any metmen in many many days... but they keep taking children of the great tree . They keep taking life wood . The smoke still rises.
— Quote from a Tree-person

Alternative Name(s)
Fifth Floor Castle, Broken Keep
Clockwork:10,000 Broken Souls:300
Inhabitant Demonym
Invicti, Clockwork Horde
The Daybreaks, Fifth Floor, Synthacrosia

War of the Fracture

Raw Materials

There are four things that Castle Invictus needs in large quantities; Ore, Wood, Water, and Food. All three of them are able to be found in The Down Deep , of which the Castle has easy access to thanks to the tunnels.  


Ore it needs to keep the Clockwork Forge running, and to keep the stream of brass Automotons flowing from the forge. The ore is broken down into usable and non-usable parts. Anything usable is melted down into the alloys required for proper clockwork construction. The non-usable parts of the ore are either discarded outside the castle walls, or used for construction and reinforcement of tunnels.  


In order to keep the fires of their forges running, the clockwork of Castle Invictus need a near constant influx of wood. So far, they've filled this need with the small trees that grow on the slops of the Daybreak Mountains. Residents of the Great Tree fear what will happen when the supply of small trees runs out, however.  

Water and Food

The Broken Souls of the Castle may be broken, but they still require food and water to live. The most deep parts of the Down Deep is where both of these required materials may be found; for in the deep, water pools and collects in dark corners. Small rodents like to congregate around these pools of water, providing the source of food for whomever needs it within the Castle.  
SSshhhhh. RRrk. Yah, you be speaking true about that. The rock dirt pile is a might bigger than before. Castle Town must be makin many more Metmen. We needa spread more Shadow-paste around, afore the Metmen see our new homes.
— Unnamed Tree-man, Fifth Floor, Great Tree


Author's Notes

Header Image via Unsplash   All images (Aside from the article header image) made by Stormbril.

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4 Jul, 2019 07:47

That was an amazing article, real nice and creepy! It was the perfect length, and everything was explained (for example, while reading the main text I was wondering where did they get all of their materials from, but you explained that later in the sidebar). I guess the only thing that was not explained was: why is it called the fifth floor castle?   There ware two minor issues and one small grammar mistake.

  • The majority of the text refers to the castle as Fifth floor, but in some areas you write Floor 5. In my opinion, is best to stick to one, to be consistent.
  • "Floor 5 has instead felt twice as many years go by; the passage of time within the floor slowing to half speed"
  • To my understanding, if time is going at half speed, those that live in the fifth floor should have experienced half as many years, not twice.
  • In this sentence, substitute "is" for "are", since the word parts is plural "The non-usable parts of the ore is either discarded outside the castle walls (...) "
  • Overall, that was a really nice twist to the industrious city prompt. You managed to tell a really good story based on it, and that is awesome!

    9 Jul, 2019 00:53

    Thank you so much! I'm finally going back to some of the comments I've received, apologies for such a late reply! It's called the Fifth Floor Castle because it's located on the Fifth Floor of Synthacrosia, no other reason really :)   As for the two issues brought up:  

  • you are 100% correct, I think it would be way better to stick to "Fifth Floor". Thanks for pointing that out!
  • and yes, time should be going at double speed, you're correct there too. I definitely put half-speed mistakenly haha!
  • and I'll go ahead and fix that little grammar mistake as well!
  • Thanks again for the wonderful comment, and the critique :)

    4 Jul, 2019 09:00

    I *really* like the opening quote: it really sets the tone about what kind of place this castle is.   I would, however, consider having a short "overview" type of paragraph above structures to give readers an idea of what kind of place it is in more detail. A floor of the tower, famous for X with Y haunting its halls, etc etc. Just a paragraph for an overview, before we dig into the rest. :)  

    Great Tree , it's massive
      Whoops, an extra space has been detected!   But as an aside, I'm always in favor of huge massive trees. If you find the space, it could be a good thing to have a blocklink to in the side panel, maybe?  
    The slopes of the Daybreak Mountains crumbled, revealing the dark, twisting, abyssal network of caves known as The Down Deep.
      Obviously, I love this part and hope to read more about that. :D   I also really enjoy the fantastical elements of your setting, like time itself being broken by the wars fought here and the things going on.  
    They were, in fact, forced out.
      You could probably nuke the ", in fact," and maybe tell us more about that? Who or what forced them out?  
    Whether suffering from Broken Core , or just evil at heart
      Another extra space. Also, *really* want to know more about clockwork cults in the future. :D   As an adventurer-engineer at heart, I wouldn't be surprised if your players try to reprogram the replicator. It's totally what I would try to do and it forms such an amazing plothook.   Your setting continues to be wonderfully weird and different. I really enjoy digging into it. Stay awesome, Stormy. <3

    Creator of Araea, Megacorpolis, and many others.
    9 Jul, 2019 00:57

    Hey Q! Always glad to have wonderful critique from you!   You bring up a great point about an overview paragraph. I think that'd really help me with what I was unhappy about with this article, as before it felt like things didnt fit together properly. Having that descriptive paragraph would help for sure!   Thank you for pointing out the extra spaces and extra words! I'm gonna hop on fixing those soon (before the end of Summer Camp at least).   Also, I totally hope my players do try to take over the clockwork forge. I want them to try to break things with it >:D   Thanks again for always being super supportive, and a beacon of inspiration. Thanks Q!

    Dryant Feywright
    4 Jul, 2019 12:36

    This is good! I love how well-thought-out it was and how the article made the content sound eerily mechanical. You know what this reminds me of? Mechanus from Dungeons & Dragons. I'd have to agree that it was left unexplained as to why it is called the Fifth Floor Castle. Perhaps it will be be explained eventually, but this article receives a Like from me! Actually no, this article is making me giving you a Follow so I can see what else I can learn about Invictus.

    9 Jul, 2019 01:01

    Thanks a bunch Dryant! I've never actually played Dungeons and Dragons, all my time is spent playing Pathfinder haha. This world is actually the world I'm constantly developing for an on-going Pathfinder campaign.   As for the name "Fifth Floor Castle", it's sadly fairly ordinary! It's called that because it exists on the Fifth Floor of Synthacrosia.   Seeing as two people brought that up, I might have to take a look at explaining that a bit better; really show that Synthacrosia is a tower, and that certain things happen on certain floors of the tower.   Thanks for the feedback!