diff --git a/src/main/java/land/chipmunk/chipmunkmod/mixin/ClientPlayerEntityMixin.java b/src/main/java/land/chipmunk/chipmunkmod/mixin/ClientPlayerEntityMixin.java
index 443030a..5e21818 100644
--- a/src/main/java/land/chipmunk/chipmunkmod/mixin/ClientPlayerEntityMixin.java
+++ b/src/main/java/land/chipmunk/chipmunkmod/mixin/ClientPlayerEntityMixin.java
@@ -2,6 +2,7 @@ package land.chipmunk.chipmunkmod.mixin;
 
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.Unique;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
@@ -16,7 +17,7 @@ import land.chipmunk.chipmunkmod.modules.CommandCore;
 
 @Mixin(ClientPlayerEntity.class)
 public class ClientPlayerEntityMixin {
-  private static MinecraftClient CLIENT = MinecraftClient.getInstance();
+  @Unique private static MinecraftClient CLIENT = MinecraftClient.getInstance();
 
   @Inject(at = @At("HEAD"), method = "move")
   public void move (MovementType type, Vec3d relPos, CallbackInfo ci) {
diff --git a/src/main/java/land/chipmunk/chipmunkmod/modules/CommandCore.java b/src/main/java/land/chipmunk/chipmunkmod/modules/CommandCore.java
index 7e5c357..c1a9309 100644
--- a/src/main/java/land/chipmunk/chipmunkmod/modules/CommandCore.java
+++ b/src/main/java/land/chipmunk/chipmunkmod/modules/CommandCore.java
@@ -8,11 +8,13 @@ import land.chipmunk.chipmunkmod.util.MathUtilities;
 import net.minecraft.block.entity.CommandBlockBlockEntity;
 import net.minecraft.client.MinecraftClient;
 import net.minecraft.client.network.ClientPlayNetworkHandler;
+import net.minecraft.client.world.ClientWorld;
 import net.minecraft.nbt.NbtCompound;
 import net.minecraft.network.ClientConnection;
 import net.minecraft.network.packet.c2s.play.UpdateCommandBlockC2SPacket;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.Vec3d;
+import net.minecraft.world.dimension.DimensionType;
 
 import java.util.Timer;
 import java.util.TimerTask;
@@ -67,21 +69,27 @@ public class CommandCore {
   }
 
   public void move (Vec3d position) {
+    final ClientWorld world = client.world;
+
+    if (world == null) return;
+
+    final DimensionType dimension = world.getDimension();
+
     origin = new BlockPos(
             ((int) position.getX() / 16) * 16,
-            (int) MathUtilities.clamp(noPos.start.getY(), client.world.getDimension().minY(), client.world.getDimension().height()),
+            (int) MathUtilities.clamp(noPos.start.getY(), dimension.minY(), dimension.height()),
             ((int) position.getZ() / 16) * 16
     );
 
     withPos = new BlockArea(
             new BlockPos(
                     noPos.start.getX() + origin.getX(),
-                    (int) MathUtilities.clamp(noPos.start.getY(), client.world.getDimension().minY(), client.world.getDimension().height()),
+                    (int) MathUtilities.clamp(noPos.start.getY(), dimension.minY(), dimension.height()),
                     noPos.start.getZ() + origin.getZ()
             ),
             new BlockPos(
                     noPos.end.getX() + origin.getX(),
-                    (int) MathUtilities.clamp(noPos.end.getY(), client.world.getDimension().minY(), client.world.getDimension().height()),
+                    (int) MathUtilities.clamp(noPos.end.getY(), dimension.minY(), dimension.height()),
                     noPos.end.getZ() + origin.getZ()
             )
     );
@@ -98,7 +106,7 @@ public class CommandCore {
   }
 
   public void refill () {
-    if (!runFillCommand) return;
+    if (!runFillCommand || withPos == null) return;
 
     final String command = String.format(
             KaboomCheck.INSTANCE.isKaboom ?
@@ -120,6 +128,8 @@ public class CommandCore {
     final BlockPos start = withPos.start;
     final BlockPos end = withPos.end;
 
+    if (start == null || end == null) return;
+
     int x = block.getX();
     int y = block.getY();
     int z = block.getZ();