Combining the "Big Three" of planetary romance—Burroughs, Brackett, and Moore—creates a Mars (or Barsoom, or Ma'adim) that is a haunting, neon-and-dust graveyard of a world. In an OSR (Old School Essentials, Dungeon World, or Worlds Without Number) context, this is a "Science-Fantasy" setting where the "dungeons" are decaying crystal cities and the "dragons" are multi-legged predators or ancient, psychic liches.
Here is a campaign framework for this dying, decadent world.
1. The Core Aesthetic: "The Dying World"
ERB’s Barsoom: Provides the action and biology. High gravity (technically low, but treated as heroic), multi-armed monsters, tharks, and the code of the sword.
Brackett’s Mars: Provides the mood and grit. Low-life spacers, dusty bazaars, ancient sins, and the oppressive heat of a failing sun.
C.L. Moore’s Mars: Provides the horror and weirdness. Shambler-haunted ruins, soul-stealing idols, and the terrifying Jirel-esque intersections of magic and science.
2. The Three Great Inhabitants
To blend these worlds, categorize the factions by their "Age":
| Faction | Origin | Vibe |
| The Red Nations | ERB | Noble but declining city-states. Great with fliers and radium rifles, but bound by rigid honor codes. |
| The Low-Canal Scum | Brackett | Terrans, outcasts, and mutants living in the "Drylands." They deal in ancient tech and forbidden drugs. |
| The Old Ones (Shamble-Men) | Moore | Immortal, degenerate sorcerers living in deep, lightless vaults. They treat humans as cattle or vessels. |
3. OSR Mechanics & Hacking
To get the right "feel" for an OSR game, you need to tweak a few standard fantasy tropes:
The "Sword vs. Radium" Rule
Technology is powerful but fickle.
Radium Pistols: Deal high damage (e.g., $2d8$) but explode on a Natural 1.
The Code: In many cities, firing a gun is a social death sentence. You duel with the longsword, or you are hunted as a coward.
Magic as Degenerate Science
There are no "Wizards." There are Mentalists (ERB) and Ancientists (Moore).
Spells are actually dormant nanotechnology, psychic projections, or "Thirsting" relics that require blood or "Life-Force" (XP) to activate.
Resource Management: The Oxygen/Water Die
In the wastes, use a Usage Die (d6 -> d4 -> Empty) for your water and oxygen supplies. If you run out in the Deep Desert, you begin taking Constitution damage every hour.
4. Key Locations (The "Hex-Crawl" Nodes)
Jha-Keel (The City of Bells): A Brackett-style trade hub built over a Moore-style abyss. It’s a hive of thieves where the bells ring to ward off "The Things from the Dark."
The Dead Sea of Korus: A Burroughs-inspired valley filled with man-eating Plant Men. It’s the ultimate "high-level" hex.
The Vault of Shambleau: A dungeon crawl where the "treasure" is a beautiful woman who is actually a psychic parasite.
5. Bestiary: The Horrors of the Red Sands
White Apes (ERB): Use Ogre stats, but give them a climbing speed and four attacks.
The Black Shadow (Moore): An incorporeal undead that drains "willpower" (Wisdom) rather than HP.
The Martian Sell-Sword (Brackett): A 3rd-level Fighter with a grudge, a radium pistol, and a heavy addiction to Keth (a Martian drug).
6. Campaign Hook: "The Last Water-Hag"
The canal systems are failing. A legendary "Water-Hag" (a Moore-style ancient) has stolen the atmospheric processors' control crystals to fuel her own immortality. The Red Nations are on the brink of a genocidal war for the last drops, while Terran syndicates are trying to strip-mine the ruins before the air runs out.
GM Tip: Emphasize the colors. Everything is ochre, crimson, violet, and dying gold. The sun is small and cold. The night is terrifyingly silent
To capture the blend of Burroughs’ heroism, Brackett’s grit, and Moore’s cosmic horror, this table is designed for a d100 roll. I’ve grouped them by "tens" to make it easier to navigate during a session.
The D100 Martian Drylands Encounter Table
| Roll (d100) | Encounter Category | Description |
| 01–10 | The Environmental Toll | Dust-devils, "Blue Fever" outbreaks, or a sudden oxygen-pocket collapse. |
| 11–30 | The Low-Canal Scum | Humanoid outlaws, Brackett-style drug runners, or Terran prospectors. |
| 31–50 | The Great Beasts | ERB-inspired megafauna: Thoats, Banths, or Zitidars. |
| 51–70 | The Fallen Aristocracy | Red Martian patrols, ruined fliers, or duelists seeking honor. |
| 71–90 | The Moore-ish Horrors | Shamblers, soul-eaters, and artifacts that hum with "wrong" geometry. |
| 91–00 | The Wonders of the Ancients | Mirage cities, functional tech-shrines, or "The Thirsting God." |
Detailed Encounters (Roll d100)
01–05: A "Dry-Storm": Vision reduced to 5 feet. Gear takes 1d4 damage from abrasive sand.
06–10: The Keth-Smugglers: 2d6 thugs (Brackett) transporting psychic drugs. They are paranoid and "twitchy."
11–20: A Thark Hunting Party: 1d10 Green Martians ($4$-armed, 15ft tall) on Thoats. They respect only strength and high-tier weaponry.
21–25: The Shambler’s Trail: A lone, wet trail of slime in the bone-dry desert. Following it leads to a Moore-style cave of "sensory bliss" and certain death.
26–30: Abandoned Radium-Schooner: A land-ship half-buried. Contains 1d6 fuel cells but is guarded by a Great White Ape.
31–40: The Duelist: A disgraced Red Martian Noble (ERB) who demands a 1-on-1 sword duel for the "right of way" through the canyon.
41–50: The Singing Towers: Ancient glass structures that emit a frequency causing $1d6$ Sanity/Wisdom damage unless ears are plugged.
51–60: A Caravan of the "Low-People": Mutant Martians selling "pre-collapse" junk. 10% chance they have a functioning Radium Rifle.
61–70: The Banth Den: 1d4 ten-legged lions stalking the party. They hunt silently and only strike at night.
71–80: The Memory-Mist: A violet fog. Anyone entering must save vs. Spells or see a vision of Mars as it was 10,000 years ago, becoming catatonic with nostalgia.
81–90: The Black God’s Idol: A Moore-esque statue that offers a "Gift" (a feat or stat boost) in exchange for the permanent sacrifice of a party member’s "Life-Spark" (Max HP reduction).
91–95: Crashed Terran Rocket: A sleek, chrome needle from Earth. 1d4 survivors are terrified and have no idea that their "currency" is worthless here.
96–99: The Sky-Galleon: A massive ERB-style warship passes overhead. If signaled, they may provide water—or a volley of radium fire.
00: The Avatar of Mars: A manifestation of the planet's dying spirit. It grants a single "Wish" but demands the players accelerate the death of a rival City-State.
Mechanics for the Drylands
Reaction Rolls: Use them! A Thark might be a lethal enemy or a staunch ally depending on a single 2d6 roll.
The "Iron Rule": If a player rolls a Natural 20 in a sword duel against a "named" NPC, they may claim that NPC's titles and holdings (Burroughs' law).
Gemini said
In the synthesis of this Mars, the Shamble-Men (derived from C.L. Moore’s Shambleau) represent the horrific, "wet" biological rot hidden beneath the "dry" red sands. They are the leftovers of an era when Martian science turned inward to solve the problem of death, resulting in a parasitic immortality.
The Nature of the Shamble-Man
They are not undead in the traditional sense; they are hyper-biological. A Shamble-Man is a humanoid host—often a beautiful youth or a wizened elder—whose nervous system has been replaced by a psychic, scarlet parasite that resembles thick, writhing hair or a mass of leeches.
The Appearance: From a distance, they look like weary travelers in heavy robes. Up close, their "hair" moves independently, and their eyes are flat, oily pits of red.
The Scent: They smell of wet earth and copper—a jarring scent in the arid Martian wastes.
OSR Stats (Generic Scale)
Hit Dice: 5+2 (The host is fragile, but the "mass" is resilient)
Armor Class: 6 [13] (Tough, rubbery hide under robes)
Attacks: 2-12 "Hair" Tendrils (1d4 each + Paralysis)
Move: 90’ (30’)
Saving Throw: F5 (Immune to sleep, charm, and mind-control)
Morale: 10
Special Abilities
The Feeding (Psychic Drain): Instead of dealing physical damage, a Shamble-Man can choose to "feed." The victim must save vs. Paralysis. On a failure, they are locked in a state of intense, agonizing euphoria. They lose 1d6 Wisdom per round. If Wisdom reaches 0, the soul is consumed, and the body becomes a fresh husk for a new Shamble-larva.
Regeneration: As long as they are feeding, they regain 1d8 HP per round.
Vulnerability: They loathe the "Cold Light of Truth." High-intensity radium flares or mirrors reflecting the Martian sun deal 2d6 damage and force a Morale check.
The "Moore-ish" Horror: The Feeding Ritual
A Shamble-Man encounter shouldn't just be a brawl. It should be a seduction.
In a Brackett-style tavern or a Burroughs-style palace, a Shamble-Man (usually in "Shambleau" form) targets the person with the highest Charisma or Strength. They offer a "forbidden ecstasy." To the victim, the experience feels like being a god; to the onlookers, it looks like a person being slowly digested by a pile of red worms.
3 Hooks for Shamble-Men
The Red Muse: A famous poet in a Red Martian city hasn't slept in weeks. He is producing masterpieces, but he’s becoming skeletal. He is hiding a "lover" in his chambers—a Shamble-Man he found in the ruins.
The Infested Mine: A Terran mining operation broke into a "Vat-Room" from the First Age. The miners haven't come out, but someone is still sending up crates of ore... packed with scarlet, pulsing moss.
The Pilgrimage: A group of "Low-People" are seen wandering into the desert, smiling and singing. They are walking toward a "Shamble-Mother," a massive, immobile biological engine that requires a village's worth of souls to birthe a new "God."
How to Kill One (The "OSR" Way)
Brute force is risky because of their Wisdom-drain. Smart players will:
Use Fire: It’s the only thing the parasite truly fears.
Reflective Shields: To bounce the harsh Martian UV rays into the dark corners where they hide.
Lead-lined Helmets: To block the psychic "song" that precedes the feeding.
In the smoke-filled "Keth-dens" of Jha-Keel or the sun-bleached plazas of a Red Martian city, information is the only currency that doesn't lose value.
Roll a d10 to see what the party overhears. Some are true, some are Brackett-style lies, and some are Moore-style warnings.
Rumors of the Red Sands
d10 The Rumor Veracity / Hook 1 "The Merchant Prince of Tharkis isn't wearing a wig. Those are scarlet tendrils. He hasn't blinked in three days." TRUE. A Shamble-man has successfully 'seated' itself in the government. 2 "There’s a downed Earth-rocket in the Sea of Silt. It was carrying a 'Positronic Brain' that knows the location of the Polar Water-Vents." PARTIAL. The 'Brain' is actually a trapped, insane Martian AI. 3 "If you drink the blue cactus milk near the Temple of Illian, you can see the invisible fliers of the Holy Assassins." FALSE. It’s just a potent hallucinogen; the assassins are very visible—and behind you. 4 "A Green Martian chieftain has found a Radium Cannon the size of a longboat. He’s looking for 'soft-skins' to help him aim it at the city walls." TRUE. This is a Burroughs-style military hook. High pay, high lethality. 5 "The 'singing' coming from the old canal pipes isn't wind. It’s the Ancientists tuning their psychic resonators for the 'Great Harvest'." TRUE. A Moore-ish ritual is reaching its crescendo beneath the city. 6 "Don't buy 'Ancient Tech' from the one-eyed trader in the bazaar. It’s all Earth-made junk painted with ochre to look like Martian bronze." TRUE. A classic Brackett-style swindle involving a "relic" that’s actually a toaster. 7 "There is a valley where the air is thick enough to breathe without a mask, but the plants there have a taste for human blood." TRUE. The Valley of Lost Souls; a dangerous hex-crawl location. 8 "The Red Princess is looking for a champion. Not for a duel, but to smuggle her out of the city before her soul is sold to the Black God." TRUE. A classic ERB-style romance hook with a Moore-ish twist. 9 "The 'Wind-Sickness' isn't a disease. It’s invisible spores from the Shamble-Mothers. If you cough up red dust, it’s already too late." TRUE. This functions as a slow-acting curse/disease mechanic for the party. 10 "Deep in the Drylands, there is a tower of pure salt. They say a Terran woman lives there who can 'sing' gold out of the sand." FALSE. It’s a psychic lure used by a Moore-ish predator to attract greedy travelers. Using these Rumors
The "Barsoom" Approach: If they follow Rumor #4 or #8, emphasize grand scale, noble gestures, and massive battles.
The "Brackett" Approach: If they follow Rumor #6 or #2, emphasize the grit, the smell of the slums, and the desperate need for credits.
The "Moore" Approach: If they follow Rumor #1, #5, or #9, dial up the body horror, the psychic dread, and the alien nature of Martian "magic."
