Many-spired Illium [Cavaliers of Mars]

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Hi, Rose here. ^_^ Thought I’d drop by with the most recent city-state I’ve redlined. Welcome to Illium, where flying ships fill the skies above and the dessicated bodies of the dead lurk in the caverns below.

Text by Rose Bailey and Meghan Fitzgerald.



High on the Radium Plateau rises many-spired Illium. Illium, city of learning and commerce… and of war. Broad, well-paved streets thread their way throughout the city, and the nights are lit by radium lamps. High white walls encircle the city, but do not rise as high as the towered homes of the aristocracy.

Great machines pump water from the canal below the plateau, through a labyrinth of caves whose layout is a closely guarded secret. The caves also hide Illium’s wondrous reclamation systems, which allow the people of the city to live with an almost unheard-of abundance of water. In Illium, there are fountains in every square, and baths in every neighborhood. The University of Illium is widely considered the greatest remaining seat of learning on Mars.

Yet plentiful water is not the true wonder of Illium. That honor belongs to the magnificent sky navy, a hundred ships buoyed by a mysterious anti-gravity element. The sky navy, docking at Illium’s highest towers and spreading forth across all of Mars, gives Illium nearly unmatched power in trade and war. Of the other city-states, only Illium’s rival Zodiac possesses the secret of flight.

A term of two years’ service in the army or navy is compulsory for citizens of Illium. Slaves may be emancipated in exchange for military service, but must serve until honorably discharged. Such discharges are usually granted only for old age.

The dead are processed for their water, and then laid to rest in the upper cave complexes. The mummies of Illium figure heavily in the scare-stories other Martians tell their children.

The Princess Invincible and her Council of Judgment rule Illium. The word of the Princess is law, and disobedience is punishable by death in the Ray Chamber. The people of Illium believe the Princess wise beyond measure… for if they thought otherwise, they might see that they live and die at the whim of an all-powerful and unaccountable goddess.


The Fortress Invincible

The Fortress Invincible may be the most heavily-defended place on Mars. Here, in her shining palace that reaches into the heavens, the Princess Invincible rules unequivocally. In the Moon Chamber, her Council of Judgment decides the fates of citizens and the shape of the city’s future. In the Ray Chamber, those who dare defy the Princess perish, disintegrated to ash in the searing heat of a First Martian weapon of devastating power. From its pier atop the Fortress’ highest spire, her own personal skyship — Horizon’s Terror — scatters these ashes on the wind over the city as a reminder to all. In the Sun Chamber, the Princess mounts her silver throne and dispenses wisdom to the people. When Illium goes to war, she draws her blade and takes to the sky with her soldiers. The sight of her ship alone has been known to send hardened troops scurrying to surrender.


  1. One of the characters turns out to look nearly identical to the Princess Invincible. They receive a myriad of proposals and offers — everything from impersonating the Princess for gain, to acting as her official body double at boring society functions, to posing with noble children for portraits.
  2. The characters are called in by the Council of Judgment, ordered to provide testimony for a crime they are meant to have witnessed. The only problem is, they didn’t witness it. Is this all a misunderstanding, or has someone embroiled them in a sticky situation on purpose?
  3. While attending the Princess in the Sun Chamber, the characters hear the plea of a family that lives out on the Radium Plateau, asking for soldiers to protect their village from roving bandits. The Princess refuses and sends them away, giving no reasons.
  4. Someone the characters know is innocent is arrested and dragged to the Fortress, destined for the Ray Chamber. Do they dare intervene, risking the same fate for themselves? Can they gather enough evidence to convince the Council before the deed is done?
  5. The characters receive an offer: go to the Sun Chamber and copy down what the Princess says into a specific book, word for word, in exchange for payment. The offer is too generous to be on the up-and-up, but the task seems so innocuous. What’s so important about this book? Why hire strangers to do such a small thing?
  6. While exploring elsewhere in the city, the characters come across a door that should lead into a storeroom, but instead leads into the Fortress’ extensive cellars. What treasures might such a place hold in store, if they can avoid getting caught? How did such a passage come to be?


  1. Captain Kromis, Red Martian second-in-command of Horizon’s Terror (Decorated Soldier X, Right Hand of Justice X, Ships Are Better than People X; Trouble: Criminal Past)
  2. Vestai of Black Sand, Red Martian noble seeking the Princess’ favor (Irresistible Good Looks X, Victory Is Worth Any Price X, Fancy Footwork X; Trouble: Glory Hound)
  3. Sebaste the August, Red Martian member of the Council of Judgment (Brood of Many Scions X, Weighty Words X, Smells a Rat X; Trouble: Hard of Hearing)
  4. Trif, Red Martian Sun Chamber petitioner (Impetuous Entrepreneur X, If Wishes Were Horses X, Lights Up the Room X; Trouble: Empty Purse)
  5. Dinni, Skarrut Ray Chamber guard (Pole Sling Master X, Heart of Stone X, Eyes of Steel X; Vitality X; Trouble: Gambling Habit)
  6. Rhes, Red Martian Moon Chamber messenger (Swift Feet X, Sixth Child of a Noble House X, Fly on the Wall X; Trouble: Sibling Rivalry)


  1. When the Ray Chamber would create a martyr or grant too quick a demise, the Princess Invincible challenges the criminal to a duel to the death. No one has ever defeated her.
  2. The Sun Chamber is a battlefield of words, where each question posed is an army’s advance and each careful greeting a tactical maneuver.
  3. Drunken beastmasters boast of a vicious, many-fanged beast with wings of enormous span that lives beneath the Fortress, kept by the Princess as a last resort against invasion or siege. (Aerial Mobility X, Toothy Maw X, Doesn’t Take Orders X)
  4. Servants at the Fortress murmur that those who wander where they shouldn’t come under a curse of confusion, doomed to forget everything they knew.
  5. Anyone who tries to stow away on Horizon’s Terror must contend with the ship’s tenacious and loyal crew.
  6. The wide plaza stretching out before the Fortress gates is prime real estate for traders hawking souvenirs and street fare with booming voices and tantalizing deals. Beware, all who planned to leave with any coin.

Sky Navy Port

The Pride of Illium, the Moonrise Fleet, the Living Storm — all of Mars knows the city’s majestic sky navy by these names, and many others besides. Its twin flagships, Scythe of Phobos and Lance of Deimos, cut distinctive and awe-inspiring figures against the sky. When the armada comes home to roost, its ships dock atop the gleaming spires of Sky Navy Port, a vast forest of towers, radium beacons, and barracks. Its shipyard is guarded fiercely day and night, protected by a high barricade and restricted to only the most trusted personnel. The fixers and builders who work on the sky navy’s ships are celebrities, and always travel with assigned bodyguards lest their secrets fall into foreign hands. The navy’s highest ranks are reserved for those of aristocratic blood, and feuds break out over promotions and medals given to rivals.


  1. By chance, the characters stumble upon a well-hidden group of dissidents among the navy’s ranks who have grown disillusioned with the Princess Invincible’s omnipotent wisdom, and plan to enlist like-minded souls to overthrow her.
  2. The navy recruits volunteers for a mission to take down infamous sky pirate and Illium deserter Cosmalia Crimson. Once the characters join up, they realize that details of the plan don’t fit together quite right. Why would the navy need volunteers to hunt pirates? What’s really going on?
  3. An admiral gives a rousing speech and the characters are part of a massive crowd assembled to hear it. As they listen, they notice that the admiral speaks oddly, as though hidden between the lines might be an encoded message. Can they decipher it?
  4. Reports of an approaching invasion force reaches the navy, and they mobilize for war. Citizens are expected to participate, and many are rounded up for emergency training at the port — including at least one of the characters.
  5. A prisoner from Illium’s last battle, kept for interrogation, escapes. The soldiers patrol the city relentlessly looking for the escapee, who approaches the characters and begs for help.
  6. The sky navy holds an auction for a newly-retired ship. While attending, the characters discover that a merchant consortium has rigged the outcome in its favor and intends to sell the ship’s technology to a foreign broker without the Princess’ permission…for an awful lot of money.


  1. Novian, Red Martian illegitimate child of nobility (Hardworking Young Soldier X, Standard Issue Blade X, I Will Win a Title X; Trouble: Seeks Acceptance)
  2. Volca (aka Qaysa), Red Martian Zodiac spy and navy infiltrator (Hoarder of Secrets X, Friend to Birds X, Crack Shot X; Trouble: Hidden Identity)
  3. Vestai of a Thousand Lights, Red Martian naval astrologer (Enigmatic Horoscope Reader X, Always on Course X, Night Owl X; Trouble: Incorrigible Dreamer)
  4. Marchai of the Valiant Horn, Red Martian admiral (Survived Ten Feuds X, Voice of Command X, Mentor to All X; Trouble: Secret Fatal Illness)
  5. Kaesii, Red Martian naval shipwright (Anti-Gravity Expert X, Bon Vivant X, Flock of Admirers X; Trouble: Common-Blooded Narcissist)
  6. Kismet, Red Martian soldier and ex-slave (Hears Everything X, Daring Maneuvers X, Born in a Far-Off Land X; Trouble: Wants Freedom and Peace)


  1. An accident at the shipyard causes the gravity in this whole area of the city to fluctuate out of control.
  2. One of the anti-gravity platforms that transports passengers up and down the tall towers malfunctions, leaving the characters stranded high above the ground.
  3. The sky navy has adopted the Princess’ dueling traditions but (usually) stops short of death. Insulting a naval officer, even by accident, is grounds for a challenge.
  4. Reports say a disturbingly large amount of photonic sand has been stolen from the armory. Whoever stole it could strike at any time.
  5. An enthusiastic shipwright asks the characters to help test an experimental weapon, but most of the kinks have yet to be worked out.
  6. A damaged ship on its way back to port is about to crash — right into the square where the characters happen to be, along with dozens of others.

University of Illium

Would-be students travel from all over Mars to the sprawling University of Illium, where if they prove themselves well enough (or they know the right people) they can study with venerated scholars of all fields: science, astrology, history, language, music, and even the secrets of the adepts. A complex, towering fountain with many levels and radium lights twinkling from within its waters graces the inner plaza. The central spire stands like an anchor around which the rest of the campus radiates in areologically-significant patterns, with lofty sky bridges connecting the structures. The spire was originally all there was to the university, one of the first buildings of Illium. Over time, it expanded to embrace the many Martians flocking to its learned halls. Today, it’s one of the few places where one might see a Roundhead and a Pale Martian sitting side by side — even if it’s only to see who can impress the Master more.


  1. The university clock tower has run continuously since the founding of the city ages ago, chiming the hours in perfect synchronization with the world’s turning. Now it’s stopped. No one knows why, but everyone knows that if it doesn’t chime the swiftly-approaching hour, something terrible will happen.
  2. The abandoned tower on the west side of campus is boarded up day and night, said to be the site of monstrous crimes in the distant past. It’s been empty as long as anyone can remember — but the characters could swear they saw someone peering down at them from the topmost window.
  3. The university is holding a city-wide competition for musicians of all kinds to prove their performing prowess. The winner is granted a significant sum of money — and perhaps more importantly, a personal audience with the Princess Invincible herself.
  4. A group of advanced students claims to have discovered, through data collected and analyzed over time, an ancient storm still writhing and thundering, raining water into a faraway canyon on the other side of the Radium Plateau. They need someone to visit the place to confirm their findings, and bring back samples.
  5. The university guards catch an assassin trying to kill one of Illium’s most renowned Masters. As the characters witness the arrest, or perhaps the intended punishment, one of them sees that the assassin is someone from their past.
  6. Only the top performers in each scholarly field win invitations to the Floating Study, an anti-gravity pavilion that takes students into the sky and away from the city. What they learn there remains a mystery, but some intrepid busybodies have dared everyone they know to sneak in and find out.


  1. Flint, Red Martian university servant (Reformed Thief X, Entrance Exam Junkie X, Cheating Is Wrong X; Trouble: Not Very Bright)
  2. Master Lipita, Roundhead scholar of antiquities (Undisputed Cydonian Expert X, Valuable Pottery Collection X, Polyglot X; Trouble: Despises Students and Strangers)
  3. Headmaster Marchai of Nebulae, Red Martian university leader (Pleasantly Cunning X, Master of Commerce X, Let’s Make a Deal X; Trouble: Overprotective Parent)
  4. Rubica, Red Martian university student (Library Addict X, Secret Stash of Relics X, Problem Solver Xl Trouble: Two Left Feet)
  5. Rezzan, Pale Martian university student (Knows Sacrifices to Every God X, Fits in Everywhere X, High Fashion X; Trouble: Tempted by Corruption)
  6. Theonin, Red Martian university student (Child of a Vestai X, Money Enough for Anything X, Tall but Meek X;  Trouble: Disastrously Untalented Adept)


  1. Two rival Masters recruit volunteers for their research, performing increasingly strange and unsettling experiments. Eventually, they turn dangerous.
  2. Hordes of large rodents called radium rats haunt the university’s alleys. Their eyes glow a dull crimson, their teeth are sharp, and they spread a radiation sickness.
  3. Students notice a bizarre shift in behavior and habits in their favorite Master, and they suspect he’s been replaced by someone — or something — else.
  4. The university claims to have one library, but in fact it has two. The second is sealed and hidden away, a prison that holds a powerful and dangerous adept.
  5. Everyone loves the new Master. Even people who just yesterday expressed the opposite. Soon, the few people on campus who don’t love the new Master know something’s wrong.
  6. A student from Zodiac enrolls with the Headmaster’s blessing. The Illium natives don’t trust or care for this turn of events, and soon things get ugly.

Plateau Caves

Beneath the city, another world stretches its fingers deep into the earth. Far from the clash of blades and chatter of markets is a subtler noise: the distant, muted rush of water gilding the silence of the tomb. Catacombs line the upper cave system for miles, where the husk-dry mummified corpses of Illium’s dead are interred after their water is removed and returned to the reclamation systems for processing. Those with money or prestige enough are buried in ornate caskets with the weapons they wielded in life, while others are simply lined up in plain stone boxes or even wrapped only in oilcloths, if stone is too rich for their family’s blood. Deeper still than Illium’s necropolis runs the elaborate network of pipes, pumps, and reclamation machines that connect the canal below to the city above and transform the fluids of the dead into clean, usable water. A spare few know how to navigate these caves, and even fewer know how to operate the machines.


  1. Somewhere inside the catacombs is a door that only seldom exists. Its surface is carved with unrecognizable runes and it vanishes unpredictably, only to return with equal capriciousness. Where does it lead? When it’s gone, where does it go? And what happens if someone is inside when it disappears?
  2. A trader from Vance persuades the characters to make their way down into the caves and study one of the reclamation machines. She calls it a “cultural exchange” and promises they’ll be rewarded handsomely for a thorough report.
  3. The characters purchase a rare and extravagant weapon, only to discover that the salesman was a fence pawning off stolen grave goods from the tomb of an influential Illian family. The family is well-known for its sorcerous ties and the characters soon realize that the weapon is cursed.


  1. Mystras, Red Martian catacomb tour guide (Illium History Buff X, Unafraid of the Dark X, Trusty Dagger X; Trouble: Morbid Curiosity)
  2. Kaniklai of Three Circles, Red Martian adept (Deadspeaker X, Renowned Mystic X, Loyal Pet Eora X; Trouble: Blind)
  3. Oea, Red Martian reclamation system engineer (Clever and Resourceful X, Down to Mars X, Tough and Muscular X; Trouble: Blunt Speech)


  1. One area of the cave system doesn’t function within the normal three spatial dimensions. Tunnels don’t lead where they should, and objects (or people) tossed down a hole fall back down from above.
  2. In the dark of the catacombs, people have been known to vanish without a trace, and some others say they hear the footsteps of the walking dead just like in the children’s tales.
  3. It’s easy to get lost under the city without a map, and maps are notoriously difficult to come by.

  4 comments for “Many-spired Illium [Cavaliers of Mars]

  1. Michael Stein
    January 26, 2016 at 11:27 pm

    Disintegration rays: what separates monarchs form God-monarchs!

    The pulp runneth over 🙂

  2. January 27, 2016 at 8:59 pm

    Outstanding stuff! I’m running this again at Gen Con next Summer. One of my buddies from Dead Gamers is also running, so two Cavaliers at Gen Con will be offered.

  3. B
    January 30, 2016 at 5:13 pm

    Is the Princess Invisible immortal or just the latest ruler in her bloodline?

    • Rose Bailey
      January 31, 2016 at 11:09 am

      Latest in her bloodline, and there’s probably been more than one dynasty. Think pharaohs.

      Now, the Witch-Queen of the Shadowed Citadel is another matter entirely…

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