Birds of War's five launch maps (Forest, Highrise, Arctic, Coliseum, Vietnam) define the Egg-raid gameplay loop, and the community has shipped custom maps within days of launch. The custom map building pipeline uses the same UE 5.6 + mod kit backbone as the custom bird pipeline, but the design constraints are different — a custom map must respect the 3v3v3 three-flock Egg-raid format, place Nests for each flock, install updraft columns, and ensure the map plays well at 9 birds per match.
This page documents the custom map building pipeline: the design constraints, the UE 5.6 editor workflow, the Nest placement system, the updraft column positioning, the lighting / audio setup, and the Steam Workshop publishing path. Pairs with the UE 5.6 mod kit beginner's guide and the custom bird creation guide.
The Three-Flock Map Design Constraint
Every Birds of War map must support three competing flocks of three birds each, with three Nests (one per flock) and a balanced Egg-spawn pattern. The design constraint is the same for every map, regardless of theme.
| Map element | Count | Placement constraint |
|---|---|---|
| Flocks | 3 | One per corner / side / center variant |
| Birds per flock | 3 | Match composition free |
| Nests | 3 | One per flock, with clear visual identity |
| Updrafts | 2–6 | Positioned for aerial combat pathways |
| Eggs | 9–15 | Distributed across the three Nests and the map center |
| Sightline breaks | Multiple | Required for Crow Shadow Flap routes |
A map that does not respect this format cannot be a competitive Birds of War map. The map will play, but matches will degenerate into one-flock dominance because the Egg-spawn pattern favors only one of the three Nests.
The Map Theme Catalogue
The launch roster has five themes. Custom maps typically extend into adjacent themes:
| Theme | Atmosphere | Existing example | Lighting palette |
|---|---|---|---|
| Forest | Dense canopy, soft light | Forest | Warm greens, ambient shadow |
| Urban / Highrise | Vertical combat, narrow ledges | Highrise | Cold teals, neon highlights |
| Arctic / Ice | Open sightlines, ice physics | Arctic | Cold blues, white reflections |
| Arena / Symmetric | Centerpiece with symmetric Nests | Coliseum | Gold / marble |
| Jungle / Dense foliage | Tropical, layered canopies | Vietnam | Hot greens, golden hour |
The community has shipped custom maps in extended themes: Desert / Canyon, Volcanic / Lava, Underwater / Coral, Sky / Floating Islands, Space / Asteroid, and Dungeon / Medieval. Each theme has the same three-flock format constraint, but the lighting / audio palette differs.
The UE 5.6 Editor Workflow
The custom map editor workflow uses the UE 5.6 editor with the Birds of War plugin enabled. The plugin adds Birds of War-specific node types and prefabs.
Step 1 — Open UE 5.6 and Create a New Project
Open Unreal Engine 5.6 from the Epic Launcher, choose New Project → Games → Blank, and pick a project location near the mod kit folder.
Step 2 — Enable the Birds of War Plugin
In the UE 5.6 editor, open Edit → Plugins and enable BirdsOfWarModKit. The plugin adds:
- Birds of War Nest actor: the placeable Nest prefab.
- Birds of War Egg spawner: the Egg-spawn point actor.
- Birds of War updraft: the updraft column actor.
- Birds of War play area: the play volume that limits the playable space.
The plugin is shipped with the mod kit and is enabled once per project.
Step 3 — Build the Map Skeleton
Build the terrain using the Landscape tool, which is the UE 5.6 standard. The recommended landscape size for a 9-bird match:
| Map scale | Landscape size | Triangles | Match length |
|---|---|---|---|
| Small (Coliseum) | 1024×1024 m | 1.4M | 4–6 minutes |
| Medium (Forest) | 2048×2048 m | 5.5M | 5–7 minutes |
| Large (Vietnam) | 4096×4096 m | 22M | 7–10 minutes |
Custom maps typically target the medium scale, which produces 5–7 minute matches that match the launch map rhythm.
Step 4 — Place the Three Nests
Place three BOW_Nest actors in a triangular arrangement. The canonical placements:
- Triangle (most common): each Nest 800–1200 m from the center, 60–90 degrees apart.
- Linear: three Nests on a line (rare; favors the middle flock).
- Asymmetric: two Nests close together, one further (favors the lone flock).
The triangle placement is the default because it produces the most-balanced Egg-raid contested zones.
Step 5 — Place the Egg Spawners
Egg spawners should be distributed:
- At each Nest: 2–3 Egg spawners near each Nest (close enough to be defended, far enough to be raidable).
- In the map center: 3–5 Egg spawners in the contested zone (the "third-flock egg pile").
- Along aerial routes: 1–2 Egg spawners along updraft columns (risky but rewarding).
The Egg-spawner placement is the single most important design choice for a custom map. A map with eggs only at Nests favors defenders; a map with eggs only in the center favors aggressive comps.
Step 6 — Place the Updrafts
Updrafts are the aerial-combat vertical mobility tool. The recommended updraft placement:
- Near each Nest: 1 updraft per Nest (for defender mobility).
- Along aerial routes: 2–3 updrafts in the contested zone (for combat surprise).
- Optional bridge updrafts: 1 updraft near any visual bridge / perch.
A map with no updrafts reduces aerial combat depth; a map with too many updrafts feels floaty.
Step 7 — Add Sightline Breaks
Sightline breaks are visual elements that block camera line-of-sight, which is the structural enabler for Crow Shadow Flap routes and audio bait play. The recommended sightline break density:
- Forest / Vietnam theme: high density (every 50 m).
- Arctic theme: low density (every 200 m); rely on updraft verticality.
- Highrise theme: medium density (every 100 m); rely on building walls.
A map without sightline breaks produces long sightlines, which favors Seagull / Eagle chip-shred pressure and disfavors Saboteur play.
Step 8 — Set Up Lighting + Audio
Lighting and audio are the polish stage. The recommended setup:
- Lighting: directional light + skylight + ambient occlusion. Avoid pure black shadows; the game reads better with warm ambient.
- Audio: ambient soundscape (wind, birds, water) + ability-specific audio cues. Avoid loud ambient sound, which competes with the proximity voice chat positional audio.
- Skybox: a believable sky that matches the theme.
The Map Polish Checklist
Before publishing, run through the polish checklist:
| Check | Pass criteria |
|---|---|
| Spawn safety | Birds spawning at the Nest are not immediately exposed to enemy crossfire |
| Egg-spawn distribution | No single Nest has access to more eggs than the others |
| Updraft distribution | Every flock has equivalent access to updrafts |
| Sightline balance | No sightline that lets one Nest snipe another |
| Performance | 60+ fps on the recommended spec (see the Windows requirements) |
| Network sync | Matches run smoothly with 9 players |
| Audio check | No audio clipping, no overpowering ambient |
| Lighting check | No pitch-black zones that hide enemies unfairly |
The polish checklist is a hard gate before publishing. Maps that fail any of these checks typically produce a single flock dominate the match, which the community reacts negatively to.
The Lighting and Audio Detail
Lighting
The Birds of War launch maps use warm-cool contrast lighting to make the flock colors readable in the air. A red Seagull on a cool-blue Highrise is highly visible; the same red Seagull on a warm-orange Coliseum blends in. Custom maps should respect this design principle.
- Warm-themed maps (Forest, Vietnam, Desert): use cool-blue accent lights to make flock colors pop.
- Cool-themed maps (Arctic, Highrise, Sky): use warm-orange accent lights.
- Arenas (Coliseum): use neutral white with directional spot lights.
Audio
The proximity voice chat is the dominant audio signal in Birds of War, which means the ambient soundscape should be quiet. The launch maps use gentle ambient (rustling leaves, distant wind, soft waves) at -20 to -30 dB. Modders should not exceed -20 dB on ambient or the proximity voice becomes unreadable.
The audio cues for Nest proximity (the "Egg nearby" sound) are built into the game's audio layer; modders should not modify them.
Steam Workshop Publishing
Custom maps publish through the same Steam Workshop flow as custom birds, but the package size is larger because of the UE 5.6 project archive.
| Map size | Project archive size | Workshop upload time |
|---|---|---|
| Small (Coliseum-tier) | ~50 MB | ~1 minute |
| Medium (Forest-tier) | ~150 MB | ~2 minutes |
| Large (Vietnam-tier) | ~400 MB | ~5 minutes |
The publishing flow is documented in detail in the Steam Workshop publishing guide.
The Launch-Week Workshop Map Showcase
The launch-week Steam Workshop has shipped several notable custom maps. The most popular community maps as of patch 1.1.5:
| Map name | Theme | Notable feature |
|---|---|---|
| Sky Garden | Floating island | Strong Saboteur routes |
| Lava Pit | Volcanic | High updraft density |
| Underwater Coral | Aquatic | First underwater map |
| Dungeon Keep | Medieval | Vertical indoor combat |
| Asteroid Belt | Space | Reduced gravity combat |
The community showcase is documented in the mod showcase page.
Common Map Mod Issues
The launch-week community has surfaced the following common issues with custom maps:
| Issue | Symptom | Fix |
|---|---|---|
| Single-Nest dominate | One flock wins most matches | Rebalance Egg-spawn distribution |
| Performance drops below 60 fps | Stuttering during Eagle dives | Reduce landscape triangle count or disable shadows |
| Network rubberbanding | Birds teleport in flight | Reduce map assets or sync rate |
| Audio echo / clipping | Audio doubles or distorts | Reduce ambient volume or use stereo spread |
| Sightline too long | One flock can see all three Nests | Add visual obstructions |
The most-frequent issue is single-Nest dominate, which is a balance issue rather than a technical issue. Modders who see this in their map should redistribute Egg spawners to balance the three Nests.
Frequently Asked Questions
What tools do I need for custom map building?
Unreal Engine 5.6 (free), the Birds of War mod kit (free), and the Birds of War plugin (ships with the kit). Optional: a 3D modeling tool for custom scenery (Blender is free).
How long does it take to make a custom map?
Roughly 30–50 hours for a polished medium-scale map with three-flock balance. Small maps can ship in 15–20 hours.
What scale should my map be?
Medium scale (2048×2048 m) is the recommended default for 5–7 minute matches. Small and large scales are viable but require more careful balance.
How many Nests do I need?
Three Nests, one per flock. The triangle placement is the most balanced.
How many updrafts should I add?
Roughly 1 updraft per Nest + 2–3 in the contested zone = 5–6 total. Too many updrafts make the map floaty.