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Going Medieval: Castle Design & Defense Architecture

Layered defense design, wall material engineering, settler mood management, and winter survival. Build a fortress that makes 20-man raids into target practice.

22 min read5,100 words2026-03-03
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Going Medieval

Your castle is your colony's last line of defense. A well-designed fortress turns a 20-man raid into target practice. A poorly designed one turns your settlers into loot. This guide covers layered defense design, material engineering, settler mood management, and winter survival — everything you need to survive and thrive in a post-Calamity medieval world.

🏰 Layered Defense Architecture

Going Medieval's Z-level system allows true vertical defense. Each layer serves a purpose.

1. Outer Curtain Wall

2 tiles thick, 3 Z-levels high. Limestone or granite only. No doors at ground level — enemies will break them in 30 seconds. Access from battlements via ladders (enemies can't climb ladders in combat). Leave a 3-tile gap between outer and inner walls — this is your kill zone.

💡 Merlons (the raised parts of battlements) give settlers +75% cover. Alternate merlon-merlon-merlon-gap for maximum firing angles.

2. Inner Killing Field

The 3-tile gap between walls. Fill with wooden traps and nothing else. No trees, no rocks, no cover. Raiders entering this zone are exposed to archers on BOTH the outer and inner wall simultaneously — crossfire doubles DPS.

💡 Place traps on every tile. A raider crossing a 3×10 killing field triggers 30 traps. Even heavy armor raiders die in 15-20 traps.

3. Inner Wall + Gatehouse

3 tiles thick, 4+ Z-levels high. Your gatehouse is the only ground-level entrance. Build a 1-tile-wide corridor through it. Line the corridor ceiling with murder holes (floor grates) — settlers on Z+1 drop rocks through them. A 5-tile corridor with murder holes kills 90% of raiders before they reach the inner door.

💡 The inner gatehouse door should be <b>iron-reinforced</b> with 2 layers (door-wall-door). If the first door breaks, retreat behind the second while archers finish from above.

4. The Keep (Last Stand)

The innermost building. Store emergency food, medicine, and backup weapons here. 3 Z-levels minimum, 3-tile-thick walls. Central staircase with barricades on every landing. If raiders reach the keep, it's a fighting retreat up the tower. Your best melee settlers hold each landing.

💡 Keep a stockpile of 500 preserved food + 200 bandages in the keep. If the outer defenses fall, your colony can survive a 10-day siege inside the keep.

🧱 Wall Material Engineering

MaterialHPBuild TimeBest For
Limestone400MediumBest all-around. Abundant, high HP, fast to build. Use for outer walls and gatehouse.
Granite600LongHighest HP. Use for the keep and inner gatehouse. Scarcer than limestone — prioritize critical structures.
Clay Brick300MediumInterior walls, settler rooms. Don't use for external defense — too fragile. Good insulation for bedrooms.
Wood150FastTemporary walls in year 1. Replace ALL wood walls with stone by year 2. Trebuchets one-shot wood.

Never Use Wood for External Walls

A single trebuchet shot destroys a wood wall instantly. Siege raiders arrive with trebuchets around year 3-4. If your outer wall is still wood when they arrive, you lose the colony. Upgrade to limestone by year 2 at the latest.

🧠 Settler Mood & Psychology

NeedMood ImpactHow to SatisfyCritical?
Hunger-30 (severe)3 food types in storage. Lavish meals if possible.⚠️ Critical
Sleep-20Individual bedrooms (5×5 minimum). No barracks past year 2 — shared rooms = mood penalty.⚠️ Critical
Temperature-15Brazier in every room. Double-thick walls for insulation. Underground rooms stay 10°C warmer in winter.Medium
Clothing-10Linen clothing (tier 1) → Leather (tier 2) → Fur-lined (tier 3 for winter). Assign warm clothes in autumn.Medium
Recreation-5Prayer spot → Shrine → Chapel. Schedule 2 hours of recreation per day. Chess table in common room.Low
Beauty-5Stone floors, tapestries on walls, statues in common areas. Wood floors give +2 beauty per tile.Low

Mood Cascade Prevention

One settler with severe mood debuffs can start a fistfight → injures another settler → their mood drops → more fights. This is a mood cascade.Prevent it by: (1) Never letting food drop below 3 days supply. (2) Isolating settlers with <20% mood in a locked room with meals until they recover. (3) Scheduling recreation time after combat — post-raid PTSD is real.

❄️ Winter Survival Guide

September

Harvest all crops. Plant nothing after September 15th — frost kills seedlings. Move livestock into covered barns (heated with braziers). Stockpile 2× winter firewood.

October

Slaughter excess livestock. Keep 1 male + 3 females. Switch all settlers to winter clothing. Double-check food stockpile: 3,000 units for 10 settlers (generous buffer for 5-month winter).

November-March

Underground living. Move all work indoors: crafting, smithing, tailoring. Outdoor work is lethal below -10°C. Settlers exposed to -20°C for 2+ hours get hypothermia (permanent health damage). Use the winter to craft and research.

April

Spring thaw. Check for frost-damaged walls. Repair before raiders arrive (spring raids start in May). Plant peas first (earliest planting — February) then wheat in March. Don't overplant — you need labor for repairs too.

The First Winter Kills Most Colonies

New players consistently underestimate winter food demand. 10 settlers × 2 meals/day × 150 days = 3,000 food. If you have fewer than 2,000 food on November 1st, start slaughtering livestock and hunting every animal on the map. Better to lose your herd than your colony.

FAQ

How thick should my outer wall be?+

2 tiles minimum. 3 tiles for sections facing the most common raid direction. At 3 tiles, trebuchets take 40+ shots to breach — enough time for your archers to kill the crew.

Why do my settlers keep having mental breaks?+

Check mood tab (click settler → mood). Most common causes: shared bedrooms (build individual rooms), eating raw food (build a kitchen), or no recreation time (schedule 2 hours of 'Anything' per day).

Best killbox design for Going Medieval?+

Unlike RimWorld, Going Medieval killboxes need verticality. A covered trench (3 tiles deep) in front of your gatehouse, lined with traps, with archers on battlements 2 Z-levels above. Raiders can't shoot up at a 45° angle — you're immune to return fire.