This blog post picks right up from What classic D&D module should I run for Barrows & Borderlands?
B4 The Lost City (1982) by Tom Moldvay (TSR)
Levels 1 - 3 (and beyond)Adapting the classic B4: The Lost City for a system like Barrows & Borderlands (a hack of Mousritter or similar OSR-adjacent games) is a fantastic project. You’re essentially shifting from "Human pulp adventure" to "Small-scale survival horror."
The tone shifts from Indiana Jones to something much more claustrophobic and desperate. Here is how to bridge the gap between the modular desert tomb and your tiny heroes.
1. The Scale Shift
In the original, the ziggurat is massive. For Barrows & Borderlands, scale is your best friend for building atmosphere.
The Environment: The "sand" of the desert feels like impassable, shifting mountains. The ziggurat isn't just a building; it’s an artificial mountain range.
Verticality: Since your characters are small, use the collapsed sections of the ziggurat to create "climbing puzzles." A broken staircase is now a treacherous cliff face requiring hooks and ropes.
2. Converting the Factions
The heart of The Lost City is the three mask-wearing factions (Cynidiceans). In a rodent-centric RPG, these shouldn't just be humans in masks—they should be different species or "afflicted" critters.
| Original Faction | B&B Interpretation | Vibe |
| Brotherhood of Gorm | The Iron-Whiskers | Stoic, armored hamsters or squirrels. They maintain the upper tiers and value "The Old Law." |
| Magi of Usamigaras | The Glitter-Paws | Illusionist mice who use shiny scavenged beads and glass. Very secretive and prone to riddles. |
| Maidens of Madarua | The Spear-Sisters | Fierce shrews or rats. They are the most proactive and likely to hire the players for "pest control" (killing Zargon’s cultists). |
3. The Monster Conversions
Standard D&D monsters are too "big" for B&B. You need to translate the threat level, not just the stats.
Zargon: Instead of a giant tentacled humanoid, imagine Zargon as a massively mutated, ancient Sludge-Toad or a monstrous, multi-eyed Star-Mole that has been warped by the pyramid's depths.
Cynidiceans: Treat them as "Hollow Ones"—creatures that have lost their spark, wandering in a drug-induced or magical stupor.
The Hive: Replace giant bees or beetles with Clockwork Scarabs or Shadow-Spiders that hunt by vibration.
4. Mechanics & Inventory Management
Burrows & Borderlands thrives on resource scarcity. The Lost City is a "resource sink" dungeon.
The Light Problem: In a tomb, light is life. If the players run out of matches or glow-moss, the "Lost" part of the title becomes very literal.
The Mask Mechanic: Make the faction masks Inventory Items. Wearing one grants "Safety" in certain zones but takes up a precious slot and might impose a "Disadvantage" on hearing or sight.
Scavenging: The Cynidicean tiers are full of "treasures" that are useless to humans but gold to mice—a rusted sewing needle (a masterwork rapier), a thimble (a sturdy helmet), or a single dried raisin (a week’s worth of iron rations).
Implementation Tip: The "Dream" State
The original module has the inhabitants living in a drug-induced haze. In B&B, you can make this more "magical." The air in the lower levels could be thick with Lotus Pollen.
Rule: Every Turn spent in a "Pollen Room" requires a Save. Failure means the PC begins to see the ruined ziggurat as a lush, golden palace, making them ignore actual traps or predators.
For a Burrows & Borderlands conversion, let’s focus on the Brotherhood of Gorm. In the original, they are the "lawful" warriors. In a rodent-centric world, they become the Gilded Sentinels—an order of aging golden hamsters who guard the upper thresholds.
Here is Kanadius, the Grandmaster of the Iron Whiskers.
Kanadius, The Last Shield-Bite
Title: Grandmaster of the Gilded Sentinels (Brotherhood of Gorm) Species: Ancient Golden Hamster Disposition: Honorable, exhausted, and slightly delusional.
Kanadius wears a heavy mask of beaten brass shaped like a stern human face. He speaks in a booming baritone that rattles his tiny ribcage, firmly believing he is a giant knight of old. He refuses to acknowledge he is a hamster living in a ruin.
Attributes & Vitals
STR: 14 | DEX: 8 | WIL: 13
HP: 8 | Armor: 2 (Ancient Plate & Brass Mask)
Morale: 10
Gear & Stashes
The Storm-Needle (Medium): A blue-tinted darning needle that crackles with static. Deals d6 damage; on a critical hit, the target is Cleaved (paralyzed) by a spark.
The Great Seal: A heavy wax-stamped coin used as a shield.
Blue Lotus Snuff: A small pouch of powder. If consumed, Kanadius ignores the first 4 points of Damage taken, but becomes "Confused" regarding friend and foe.
Behavior & Traits
Oath-Bound: Kanadius will not attack unless the party violates the "Sanctity of the Threshold" (the entrance to Level 2) or refuses to bow to the Altar of Gorm.
Diminished Sight: Due to his heavy brass mask, Kanadius has Disadvantage on any checks involving sight or ranged reaction, but Advantage on saves against Fear or Mind-Control.
The Golden Haze: He often speaks to people who aren't there—specifically his "fallen legion."
Quest Hook: "The Iron Thimble"
Kanadius will grant the party passage and a Silver Map of the Upper Tier if they retrieve his lost "Great Helm" (a rusted metal thimble) from a nest of Shadow-Shrews in the ventilation shafts.
How to Roleplay Kanadius
The Voice: Deep, raspy, and overly formal. Use words like "thee," "thou," and "interloper."
The Twitch: Despite his stoicism, his nose twitches uncontrollably when he smells fresh seeds or dried fruit, breaking his "noble knight" persona for a brief, embarrassing second.
GM Note: If the players manage to unmask Kanadius, his Morale immediately drops to 4. Without the mask, he realizes the world is dark, terrifying, and small, and he will likely flee to the nearest crevice.
Gemini said
Since Burrows & Borderlands is all about making the most of "human-sized" debris, this table focuses on the unique, gritty utility of a ruined ziggurat.
Rolling a d100 gives you a mix of survival essentials, "high-tier" gear for rodents, and evocative flavor that reinforces the scale.
The Cynidicean Scavenge Table (d100)
How to use this table:
Searching Tiers: For every 10 minutes (1 Turn) spent searching a room, have a player roll.
The Weight of Loot: Remember that in B&B, many of these items (like the Marble or the Matchstick) are Heavy and might take up 2 slots or require two mice to carry.
Flavoring the Finds: Describe the dust and the smell of ancient cedar as they pull these "relics" from the sand.