diff --git a/core/src/mindustry/core/ContentLoader.java b/core/src/mindustry/core/ContentLoader.java
index aa5fe5ba44..3a3fe0d2a3 100644
--- a/core/src/mindustry/core/ContentLoader.java
+++ b/core/src/mindustry/core/ContentLoader.java
@@ -167,10 +167,6 @@ public class ContentLoader{
     }
 
     public void handleContent(Content content){
-        if(content instanceof Item && content.id > 255){
-            throw new IllegalArgumentException("You may not have more than 255 different items total. Remove some mods.");
-        }
-
         this.lastAdded = content;
         contentMap[content.getContentType().ordinal()].add(content);
     }
diff --git a/core/src/mindustry/entities/comp/BuildingComp.java b/core/src/mindustry/entities/comp/BuildingComp.java
index f77183dba4..e498ab4701 100644
--- a/core/src/mindustry/entities/comp/BuildingComp.java
+++ b/core/src/mindustry/entities/comp/BuildingComp.java
@@ -135,8 +135,9 @@ abstract class BuildingComp implements Posc, Teamc, Healthc, Buildingc, Timerc,
 
     public final void writeBase(Writes write){
         write.f(health);
-        write.b(rotation);
+        write.b(rotation | 0b10000000);
         write.b(team.id);
+        write.b(0); //extra padding for later use
         if(items != null) items.write(write);
         if(power != null) power.write(write);
         if(liquids != null) liquids.write(write);
@@ -145,12 +146,20 @@ abstract class BuildingComp implements Posc, Teamc, Healthc, Buildingc, Timerc,
 
     public final void readBase(Reads read){
         health = read.f();
-        rotation = read.b();
+        byte rot = read.b();
         team = Team.get(read.b());
-        if(items != null) items.read(read);
-        if(power != null) power.read(read);
-        if(liquids != null) liquids.read(read);
-        if(cons != null) cons.read(read);
+
+        rotation = rot & 0b01111111;
+        boolean legacy = true;
+        if((rot & 0b10000000) != 0){
+            read.b(); //padding
+            legacy = false;
+        }
+
+        if(items != null) items.read(read, legacy);
+        if(power != null) power.read(read, legacy);
+        if(liquids != null) liquids.read(read, legacy);
+        if(cons != null) cons.read(read, legacy);
     }
 
     public void writeAll(Writes write){
diff --git a/core/src/mindustry/io/legacy/LegacySaveVersion.java b/core/src/mindustry/io/legacy/LegacySaveVersion.java
index 7e78855f7e..74e4a12286 100644
--- a/core/src/mindustry/io/legacy/LegacySaveVersion.java
+++ b/core/src/mindustry/io/legacy/LegacySaveVersion.java
@@ -74,10 +74,10 @@ public abstract class LegacySaveVersion extends SaveVersion{
                             tile.setTeam(Team.get(team));
                             tile.build.rotation = rotation;
 
-                            if(tile.build.items != null) tile.build.items.read(Reads.get(stream));
-                            if(tile.build.power != null) tile.build.power.read(Reads.get(stream));
-                            if(tile.build.liquids != null) tile.build.liquids.read(Reads.get(stream));
-                            if(tile.build.cons != null) tile.build.cons.read(Reads.get(stream));
+                            if(tile.build.items != null) tile.build.items.read(Reads.get(stream), true);
+                            if(tile.build.power != null) tile.build.power.read(Reads.get(stream), true);
+                            if(tile.build.liquids != null) tile.build.liquids.read(Reads.get(stream), true);
+                            if(tile.build.cons != null) tile.build.cons.read(Reads.get(stream), true);
 
                             //read only from subclasses!
                             tile.build.read(Reads.get(in), version);
diff --git a/core/src/mindustry/world/blocks/defense/turrets/ItemTurret.java b/core/src/mindustry/world/blocks/defense/turrets/ItemTurret.java
index 5fa0e70947..8a902510bc 100644
--- a/core/src/mindustry/world/blocks/defense/turrets/ItemTurret.java
+++ b/core/src/mindustry/world/blocks/defense/turrets/ItemTurret.java
@@ -138,13 +138,18 @@ public class ItemTurret extends Turret{
             return ammoTypes.get(item) != null && totalAmmo + ammoTypes.get(item).ammoMultiplier <= maxAmmo;
         }
 
+        @Override
+        public byte version(){
+            return 2;
+        }
+
         @Override
         public void write(Writes write){
             super.write(write);
             write.b(ammo.size);
             for(AmmoEntry entry : ammo){
                 ItemEntry i = (ItemEntry)entry;
-                write.b(i.item.id);
+                write.s(i.item.id);
                 write.s(i.amount);
             }
         }
@@ -154,7 +159,7 @@ public class ItemTurret extends Turret{
             super.read(read, revision);
             int amount = read.ub();
             for(int i = 0; i < amount; i++){
-                Item item = Vars.content.item(read.ub());
+                Item item = Vars.content.item(revision < 2 ? read.ub() : read.s());
                 short a = read.s();
                 totalAmmo += a;
                 ammo.add(new ItemEntry(item, a));
diff --git a/core/src/mindustry/world/blocks/defense/turrets/Turret.java b/core/src/mindustry/world/blocks/defense/turrets/Turret.java
index 99de204e4e..af49518ac3 100644
--- a/core/src/mindustry/world/blocks/defense/turrets/Turret.java
+++ b/core/src/mindustry/world/blocks/defense/turrets/Turret.java
@@ -436,7 +436,7 @@ public abstract class Turret extends Block{
         public void read(Reads read, byte revision){
             super.read(read, revision);
 
-            if(revision == 1){
+            if(revision >= 1){
                 reload = read.f();
                 rotation = read.f();
             }
diff --git a/core/src/mindustry/world/blocks/sandbox/LiquidSource.java b/core/src/mindustry/world/blocks/sandbox/LiquidSource.java
index 10f7ff2710..ce5d657527 100644
--- a/core/src/mindustry/world/blocks/sandbox/LiquidSource.java
+++ b/core/src/mindustry/world/blocks/sandbox/LiquidSource.java
@@ -87,16 +87,21 @@ public class LiquidSource extends Block{
             return source;
         }
 
+        @Override
+        public byte version(){
+            return 1;
+        }
+
         @Override
         public void write(Writes write){
             super.write(write);
-            write.b(source == null ? -1 : source.id);
+            write.s(source == null ? -1 : source.id);
         }
 
         @Override
         public void read(Reads read, byte revision){
             super.read(read, revision);
-            byte id = read.b();
+            int id = revision == 1 ? read.s() : read.b();
             source = id == -1 ? null : content.liquid(id);
         }
     }
diff --git a/core/src/mindustry/world/blocks/storage/Unloader.java b/core/src/mindustry/world/blocks/storage/Unloader.java
index cb1c40b860..1ca83e08d4 100644
--- a/core/src/mindustry/world/blocks/storage/Unloader.java
+++ b/core/src/mindustry/world/blocks/storage/Unloader.java
@@ -107,16 +107,21 @@ public class Unloader extends Block{
             return sortItem;
         }
 
+        @Override
+        public byte version(){
+            return 1;
+        }
+
         @Override
         public void write(Writes write){
             super.write(write);
-            write.b(sortItem == null ? -1 : sortItem.id);
+            write.s(sortItem == null ? -1 : sortItem.id);
         }
 
         @Override
         public void read(Reads read, byte revision){
             super.read(read, revision);
-            byte id = read.b();
+            int id = revision == 1 ? read.s() : read.b();
             sortItem = id == -1 ? null : content.items().get(id);
         }
     }
diff --git a/core/src/mindustry/world/modules/BlockModule.java b/core/src/mindustry/world/modules/BlockModule.java
index 974f43656f..fc61966a46 100644
--- a/core/src/mindustry/world/modules/BlockModule.java
+++ b/core/src/mindustry/world/modules/BlockModule.java
@@ -5,5 +5,12 @@ import arc.util.io.*;
 /** A class that represents compartmentalized tile entity state. */
 public abstract class BlockModule{
     public abstract void write(Writes write);
-    public abstract void read(Reads read);
+
+    public void read(Reads read, boolean legacy){
+        read(read);
+    }
+
+    public void read(Reads read){
+        read(read, false);
+    }
 }
diff --git a/core/src/mindustry/world/modules/ItemModule.java b/core/src/mindustry/world/modules/ItemModule.java
index 23a2b88745..52fdd63dfd 100644
--- a/core/src/mindustry/world/modules/ItemModule.java
+++ b/core/src/mindustry/world/modules/ItemModule.java
@@ -276,30 +276,30 @@ public class ItemModule extends BlockModule{
 
     @Override
     public void write(Writes write){
-        byte amount = 0;
+        int amount = 0;
         for(int item : items){
             if(item > 0) amount++;
         }
 
-        write.b(amount); //amount of items
+        write.s(amount); //amount of items
 
         for(int i = 0; i < items.length; i++){
             if(items[i] > 0){
-                write.b(i); //item ID
+                write.s(i); //item ID
                 write.i(items[i]); //item amount
             }
         }
     }
 
     @Override
-    public void read(Reads read){
+    public void read(Reads read, boolean legacy){
         //just in case, reset items
         Arrays.fill(items, 0);
-        int count = read.ub();
+        int count = legacy ? read.ub() : read.s();
         total = 0;
 
         for(int j = 0; j < count; j++){
-            int itemid = read.ub();
+            int itemid = legacy ? read.ub() : read.s();
             int itemamount = read.i();
             items[content.item(itemid).id] = itemamount;
             total += itemamount;
diff --git a/core/src/mindustry/world/modules/LiquidModule.java b/core/src/mindustry/world/modules/LiquidModule.java
index b2fbb3407a..292df3198a 100644
--- a/core/src/mindustry/world/modules/LiquidModule.java
+++ b/core/src/mindustry/world/modules/LiquidModule.java
@@ -114,29 +114,29 @@ public class LiquidModule extends BlockModule{
 
     @Override
     public void write(Writes write){
-        byte amount = 0;
+        int amount = 0;
         for(float liquid : liquids){
             if(liquid > 0) amount++;
         }
 
-        write.b(amount); //amount of liquids
+        write.s(amount); //amount of liquids
 
         for(int i = 0; i < liquids.length; i++){
             if(liquids[i] > 0){
-                write.b(i); //liquid ID
-                write.f(liquids[i]); //item amount
+                write.s(i); //liquid ID
+                write.f(liquids[i]); //liquid amount
             }
         }
     }
 
     @Override
-    public void read(Reads read){
+    public void read(Reads read, boolean legacy){
         Arrays.fill(liquids, 0);
         total = 0f;
-        int count = read.ub();
+        int count = legacy ? read.ub() : read.s();
 
         for(int j = 0; j < count; j++){
-            int liquidid = read.ub();
+            int liquidid = legacy ? read.ub() : read.s();
             float amount = read.f();
             liquids[liquidid] = amount;
             if(amount > 0){