diff --git a/core/assets/bundles/bundle.properties b/core/assets/bundles/bundle.properties
index 2cb62f7456..4d0191c9d7 100644
--- a/core/assets/bundles/bundle.properties
+++ b/core/assets/bundles/bundle.properties
@@ -586,7 +586,7 @@ objective.enemiesapproaching = [accent]Enemies approaching in [lightgray]{0}[]
 objective.destroycore = [accent]Destroy Enemy Core
 objective.command = [accent]Command Units
 objective.nuclearlaunch = [accent]\u26a0 Nuclear launch detected: [lightgray]{0}
-announce.nuclearstrike = [scarlet]\u26a0 NUCLEAR STRIKE INBOUND \u26a0
+announce.nuclearstrike = [red]\u26a0 NUCLEAR STRIKE INBOUND \u26a0
 
 loadout = Loadout
 resources = Resources
diff --git a/core/assets/maps/three.msav b/core/assets/maps/three.msav
index 88ec17deda..cd4686c856 100644
Binary files a/core/assets/maps/three.msav and b/core/assets/maps/three.msav differ
diff --git a/core/src/mindustry/content/Blocks.java b/core/src/mindustry/content/Blocks.java
index 85a9f559c5..765096bf0f 100644
--- a/core/src/mindustry/content/Blocks.java
+++ b/core/src/mindustry/content/Blocks.java
@@ -4159,6 +4159,7 @@ public class Blocks{
             consumeItems(with(Items.silicon, 50, Items.tungsten, 40));
 
             constructTime = 60f * 40f;
+            researchCostMultiplier = 0.75f;
 
             upgrades.addAll(
             new UnitType[]{UnitTypes.stell, UnitTypes.latum}
diff --git a/core/src/mindustry/content/ErekirTechTree.java b/core/src/mindustry/content/ErekirTechTree.java
index 48c966d62f..cadc56eafb 100644
--- a/core/src/mindustry/content/ErekirTechTree.java
+++ b/core/src/mindustry/content/ErekirTechTree.java
@@ -188,7 +188,7 @@ public class ErekirTechTree{
                 node(cliffCrusher, () -> {
                     node(siliconArcFurnace, () -> {
                         node(electrolyzer, Seq.with(new OnSector(three)), () -> {
-                            node(oxidationChamber, Seq.with(new Research(mechReconstructor)), () -> {
+                            node(oxidationChamber, Seq.with(new Research(mechReconstructor), new OnSector(four)), () -> {
                                 node(electricHeater, Seq.with(new OnSector(four)), () -> {
                                     node(heatRedirector, () -> {
 
diff --git a/core/src/mindustry/content/SectorPresets.java b/core/src/mindustry/content/SectorPresets.java
index 3e027a2a0c..7f3fe5c6b4 100644
--- a/core/src/mindustry/content/SectorPresets.java
+++ b/core/src/mindustry/content/SectorPresets.java
@@ -207,9 +207,10 @@ public class SectorPresets{
 
             rules = r -> {
                 r.objectives.addAll(
-                    new DestroyBlocksObjective(Blocks.coreBastion, Team.malis, Point2.pack(290,501), Point2.pack(158,496)),
+                    new DestroyBlocksObjective(Blocks.coreBastion, Team.malis, Point2.pack(290,501), Point2.pack(158,496))
+                    .withFlags("nukeannounce"),
                     new TimerObjective("@objective.nuclearlaunch", 4 * 60 * 60).withMarkers(
-                        new TextMarker("Evacuate base", 1, 1),
+                        new TextMarker("[red]Evacuate immediately.", 338 * 8f, 378 * 8f),
                         new MinimapMarker(338, 378, 50f, 14f, Pal.remove)
                     ).withFlags("nuke1")
                 );