Fixed #7874

core/src/mindustry/content/Blocks.java

@@ -3956,6 +3956,7 @@ public class Blocks{
             coolantMultiplier = 6f;
             shootSound = Sounds.shootAlt;
 
+            targetUnderBlocks = false;
             shake = 1f;
             ammoPerShot = 2;
             drawer = new DrawTurret("reinforced-");
@@ -4006,6 +4007,7 @@ public class Blocks{
             ammoPerShot = 3;
             maxAmmo = 30;
             consumeAmmoOnce = true;
+            targetUnderBlocks = false;
 
             shootSound = Sounds.shootAltLong;
 
@@ -4606,6 +4608,7 @@ public class Blocks{
             minWarmup = 0.94f;
             shootWarmupSpeed = 0.03f;
             targetAir = false;
+            targetUnderBlocks = false;
 
             shake = 6f;
             ammoPerShot = 20;

core/src/mindustry/core/NetServer.java

@@ -226,6 +226,14 @@ public class NetServer implements ApplicationListener{
                     con.kick(KickReason.idInUse);
                     return;
                 }
+
+                for(var otherCon : net.getConnections()){
+                    if(otherCon != con && uuid.equals(otherCon.uuid)){
+                        con.uuid = packet.uuid;
+                        con.kick(KickReason.idInUse);
+                        return;
+                    }
+                }
             }
 
             packet.name = fixName(packet.name);

core/src/mindustry/world/blocks/defense/turrets/Turret.java

@@ -81,12 +81,14 @@ public class Turret extends ReloadTurret{
     public boolean playerControllable = true;
     /** If true, this block will display ammo multipliers in its stats (irrelevant for certain types of turrets). */
     public boolean displayAmmoMultiplier = true;
+    /** If false, 'under' blocks like conveyors are not targeted. */
+    public boolean targetUnderBlocks = true;
     /** Function for choosing which unit to target. */
     public Sortf unitSort = UnitSorts.closest;
     /** Filter for types of units to attack. */
     public Boolf<Unit> unitFilter = u -> true;
     /** Filter for types of buildings to attack. */
-    public Boolf<Building> buildingFilter = b -> !b.block.underBullets;
+    public Boolf<Building> buildingFilter = b -> targetUnderBlocks || !b.block.underBullets;
 
     /** Color of heat region drawn on top (if found) */
     public Color heatColor = Pal.turretHeat;