diff --git a/core/assets/maps/origin.msav b/core/assets/maps/origin.msav
index 2a9c6c87a9..f17535e0c3 100644
Binary files a/core/assets/maps/origin.msav and b/core/assets/maps/origin.msav differ
diff --git a/core/src/mindustry/ai/types/BuilderAI.java b/core/src/mindustry/ai/types/BuilderAI.java
index 66e326042a..cc3eb8565c 100644
--- a/core/src/mindustry/ai/types/BuilderAI.java
+++ b/core/src/mindustry/ai/types/BuilderAI.java
@@ -158,8 +158,7 @@ public class BuilderAI extends AIController{
                 }
             }
 
-            //TODO this is bad, rebuild time should not depend on AI here
-            float rebuildTime = (unit.team.rules().rtsAi ? 8f : 2f) * 60f;
+            float rebuildTime = 2f * 60f;
 
             //find new plan
             if(!onlyAssist && !unit.team.data().plans.isEmpty() && following == null && timer.get(timerTarget3, rebuildTime)){
diff --git a/core/src/mindustry/content/ErekirTechTree.java b/core/src/mindustry/content/ErekirTechTree.java
index f96e10ee2c..346d4bb6f0 100644
--- a/core/src/mindustry/content/ErekirTechTree.java
+++ b/core/src/mindustry/content/ErekirTechTree.java
@@ -385,7 +385,9 @@ public class ErekirTechTree{
                                                     node(siege, Seq.with(new SectorComplete(crevice)), () -> {
                                                         node(crossroads, Seq.with(new SectorComplete(siege)), () -> {
                                                             node(karst, Seq.with(new SectorComplete(crossroads), new Research(coreAcropolis)), () -> {
+                                                                node(origin, Seq.with(new SectorComplete(karst), new Research(coreAcropolis), new Research(UnitTypes.vanquish), new Research(UnitTypes.disrupt), new Research(UnitTypes.collaris)), () -> {
 
+                                                                });
                                                             });
                                                         });
                                                     });
diff --git a/core/src/mindustry/content/Planets.java b/core/src/mindustry/content/Planets.java
index 027e30280c..3c753818ec 100644
--- a/core/src/mindustry/content/Planets.java
+++ b/core/src/mindustry/content/Planets.java
@@ -66,6 +66,7 @@ public class Planets{
             defaultCore = Blocks.coreBastion;
             iconColor = Color.valueOf("ff9266");
             hiddenItems.addAll(Items.serpuloItems).removeAll(Items.erekirItems);
+            enemyBuildSpeedMultiplier = 0.4f;
 
             //TODO SHOULD there be lighting?
             updateLighting = false;
diff --git a/core/src/mindustry/content/SectorPresets.java b/core/src/mindustry/content/SectorPresets.java
index dc824c5444..8069c135d6 100644
--- a/core/src/mindustry/content/SectorPresets.java
+++ b/core/src/mindustry/content/SectorPresets.java
@@ -12,8 +12,8 @@ public class SectorPresets{
     impact0078, desolateRift, nuclearComplex, planetaryTerminal,
     coastline, navalFortress,
 
-    onset, aegis, lake, intersect, basin, atlas, split, marsh, peaks, ravine, caldera, stronghold, crevice, siege,
-            crossroads, karst;
+    onset, aegis, lake, intersect, basin, atlas, split, marsh, peaks, ravine, caldera,
+    stronghold, crevice, siege, crossroads, karst, origin;
 
     public static void load(){
         //region serpulo
@@ -181,6 +181,10 @@ public class SectorPresets{
             captureWave = 10;
         }};
 
+        origin = new SectorPreset("origin", erekir, 12){{
+            difficulty = 10;
+        }};
+
         //endregion
     }
 }
diff --git a/core/src/mindustry/core/Logic.java b/core/src/mindustry/core/Logic.java
index ab136b717a..1179c61c4c 100644
--- a/core/src/mindustry/core/Logic.java
+++ b/core/src/mindustry/core/Logic.java
@@ -133,6 +133,7 @@ public class Logic implements ApplicationListener{
 
                 state.rules.coreIncinerates = true;
                 state.rules.waveTeam.rules().infiniteResources = true;
+                state.rules.waveTeam.rules().buildSpeedMultiplier *= state.getPlanet().enemyBuildSpeedMultiplier;
 
                 //fill enemy cores by default? TODO decide
                 for(var core : state.rules.waveTeam.cores()){
diff --git a/core/src/mindustry/type/Planet.java b/core/src/mindustry/type/Planet.java
index 892e147851..14546fcd4b 100644
--- a/core/src/mindustry/type/Planet.java
+++ b/core/src/mindustry/type/Planet.java
@@ -103,6 +103,8 @@ public class Planet extends UnlockableContent{
     public boolean allowSectorInvasion = false;
     /** If true, sectors saves are cleared when lost. */
     public boolean clearSectorOnLose = false;
+    /** Multiplier for enemy rebuild speeds; only applied in campaign (not standard rules) */
+    public float enemyBuildSpeedMultiplier = 1f;
     /** If true, enemy cores are replaced with spawnpoints on this planet (for invasions) */
     public boolean enemyCoreSpawnReplace = false;
     /** If true, blocks in the radius of the core will be removed and "built up" in a shockwave upon landing. */