diff --git a/core/src/mindustry/game/Universe.java b/core/src/mindustry/game/Universe.java
index 4aa77d8be7..7466fb846e 100644
--- a/core/src/mindustry/game/Universe.java
+++ b/core/src/mindustry/game/Universe.java
@@ -253,7 +253,7 @@ public void runTurn(){
 
                     //queue random invasions
                     if(!sector.isAttacked() && sector.planet.allowSectorInvasion && sector.info.minutesCaptured > invasionGracePeriod && sector.info.hasSpawns){
-                        int count = sector.near().count(s -> s.hasEnemyBase() && !s.hasBase());
+                        int count = sector.nearbyEnemyBases();
 
                         //invasion chance depends on # of nearby bases
                         if(count > 0 && Mathf.chance(baseInvasionChance * (0.8f + (count - 1) * 0.3f))){
diff --git a/core/src/mindustry/graphics/OverlayRenderer.java b/core/src/mindustry/graphics/OverlayRenderer.java
index 22b26cd0ef..396c9c26e9 100644
--- a/core/src/mindustry/graphics/OverlayRenderer.java
+++ b/core/src/mindustry/graphics/OverlayRenderer.java
@@ -235,14 +235,14 @@ public void drawTop(){
         Lines.stroke(2f);
         Draw.color(Color.gray, Color.lightGray, Mathf.absin(Time.time, 8f, 1f));
 
-        if(state.hasSpawns()){
+        if(state.hasSpawns() || state.hasSector() && state.getSector().vulnerable()){
             Core.camera.bounds(Tmp.r1);
             boolean isBuilding = input.isBreaking() || input.isPlacing() || input.selectPlans.any() || Core.settings.getBool("alwaysshowdropzone", true);
-            int r = state.rules.dropZoneRadius;
+            float r = state.rules.dropZoneRadius;
             for(Tile tile : spawner.getSpawns()){
                 if(tile.within(player.x, player.y, r + spawnerMargin) || (Tmp.r1.overlaps(tile.getX() - r, tile.getY() - r, r * 2, r * 2) && isBuilding)){
-                    Draw.alpha(building ? 1 : Mathf.clamp(1f - (player.dst(tile) - state.rules.dropZoneRadius) / spawnerMargin));
-                    Lines.dashCircle(tile.worldx(), tile.worldy(), state.rules.dropZoneRadius);
+                    Draw.alpha(!state.hasSpawns() ? 0.3 : isBuilding ? 1 : Mathf.clamp(1f - (player.dst(tile) - r) / spawnerMargin));
+                    Lines.dashCircle(tile.worldx(), tile.worldy(), r);
                 }
             }
         }
diff --git a/core/src/mindustry/type/Sector.java b/core/src/mindustry/type/Sector.java
index 921802e389..9a7e50c5ff 100644
--- a/core/src/mindustry/type/Sector.java
+++ b/core/src/mindustry/type/Sector.java
@@ -65,6 +65,28 @@ public void near(Cons<Sector> cons){
         }
     }
 
+    public int nearbyEnemyBases(){
+        int bases = 0;
+        for(Ptile tile : tile.tiles){
+            Sector s = planet.getSector(tile);
+            if(s.hasEnemyBase() && !s.hasBase()){
+                bases ++;
+            }
+        }
+        return bases;
+    }
+
+    public boolean vulnerable(){
+        if(!planet.allowSectorInvasion) return false;
+        for(Ptile tile : tile.tiles){
+            Sector s = planet.getSector(tile);
+            if(s.hasEnemyBase() && !s.hasBase()){
+                return true;
+            }
+        }
+        return false;
+    }
+
     /** Displays threat as a formatted string. */
     public String displayThreat(){
         float step = 0.25f;