diff --git a/build.gradle b/build.gradle
index 412b62d..3493d78 100644
--- a/build.gradle
+++ b/build.gradle
@@ -150,17 +150,26 @@ task generateAssets {
 }
 
 shadowJar {
+    def manifestAttributes = [:]
+    manifestAttributes += ["FMLCorePluginContainsFMLMod" : true]
+
+    if(accessTransformersFile.isEmpty() == false) {
+        manifestAttributes += ["FMLAT" : accessTransformersFile.toString()]
+    }
+
     if(usesMixins.toBoolean()) {
         from refMap
         manifest {
-            attributes([
-                    "TweakClass"                 : "org.spongepowered.asm.launch.MixinTweaker",
-                    "MixinConfigs"               : mixinConfigJson,
-                    "FMLCorePluginContainsFMLMod": true,
-                    "ForceLoadAsMod"             : loadNormalModAfterApplingMixins.toBoolean()
-            ])
+            manifestAttributes += [
+                    "TweakClass" : "org.spongepowered.asm.launch.MixinTweaker",
+                    "MixinConfigs" : mixinConfigJson,
+                    "ForceLoadAsMod" : loadNormalModAfterApplingMixins.toBoolean()
+            ]
         }
     }
+    manifest {
+        attributes(manifestAttributes)
+    }
 
     minimize()
     configurations = [project.configurations.shadowImplementation]
@@ -168,17 +177,26 @@ shadowJar {
 }
 
 jar {
+    def manifestAttributes = [:]
+    manifestAttributes += ["FMLCorePluginContainsFMLMod" : true]
+
+    if(accessTransformersFile.isEmpty() == false) {
+        manifestAttributes += ["FMLAT" : accessTransformersFile.toString()]
+    }
+
     if(usesMixins.toBoolean()) {
         from refMap
         manifest {
-            attributes([
-                    "TweakClass"                 : "org.spongepowered.asm.launch.MixinTweaker",
-                    "MixinConfigs"               : mixinConfigJson,
-                    "FMLCorePluginContainsFMLMod": true,
-                    "ForceLoadAsMod"             : loadNormalModAfterApplingMixins.toBoolean()
-            ])
+            manifestAttributes += [
+                    "TweakClass" : "org.spongepowered.asm.launch.MixinTweaker",
+                    "MixinConfigs" : mixinConfigJson,
+                    "ForceLoadAsMod" : loadNormalModAfterApplingMixins.toBoolean()
+            ]
         }
     }
+    manifest {
+        attributes(manifestAttributes)
+    }
 
     if(usesShadowedDependencies.toBoolean()) {
         dependsOn(shadowJar)
diff --git a/gradle.properties b/gradle.properties
index 137898a..0cd6999 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -28,6 +28,10 @@ gradleTokenGroupName = GRADLETOKEN_GROUPNAME
 # Example value: apiPackage = api + modGroup = com.myname.mymodid -> com.myname.mymodid.api
 apiPackage =
 
+# Specify the configuration file for Forge's access transformers here. I must be placed into /src/main/resources/META-INF/
+# Example value: mymodid_at.cfg
+accessTransformersFile = mymodid_at.cfg
+
 # Provides setup for Mixins if enabled. If you don't know what mixins are: Keep it disabled!
 usesMixins = true
 # Specify the location of your implementation of IMixinPlugin. Leave it empty otherwise.
diff --git a/src/main/java/com/myname/mymodid/CommonProxy.java b/src/main/java/com/myname/mymodid/CommonProxy.java
index 5c5ef7d..165825c 100644
--- a/src/main/java/com/myname/mymodid/CommonProxy.java
+++ b/src/main/java/com/myname/mymodid/CommonProxy.java
@@ -1,6 +1,9 @@
 package com.myname.mymodid;
 
 import cpw.mods.fml.common.event.*;
+import net.minecraft.block.material.Material;
+import net.minecraft.client.gui.GuiScreenBook;
+import net.minecraft.init.Blocks;
 
 public class CommonProxy {
 
@@ -20,7 +23,14 @@ public class CommonProxy {
 
     // postInit "Handle interaction with other mods, complete your setup based on this."
     public void postInit(FMLPostInitializationEvent event) {
+        // Access originally package-private subclass
+        GuiScreenBook.NextPageButton button = null;
 
+        // Access originally private field
+        Material air = Blocks.air.blockMaterial;
+
+        // Access originally protected method
+        Blocks.air.disableStats();
     }
 
     public void serverAboutToStart(FMLServerAboutToStartEvent event) {
diff --git a/src/main/resources/META-INF/mymodid_at.cfg b/src/main/resources/META-INF/mymodid_at.cfg
new file mode 100644
index 0000000..1e7afd5
--- /dev/null
+++ b/src/main/resources/META-INF/mymodid_at.cfg
@@ -0,0 +1,17 @@
+# Override visibility of Vanilla Minecraft code only! It will not work on mods!
+
+# Warning: Whenever you change this file you must run 'setupDecompWorkspace' again and afterwards reimport the gradle project!
+
+# https://mcforge.readthedocs.io/en/latest/advanced/accesstransformers/
+
+# Classes
+# <access modifier> <fully qualified class name>
+public net.minecraft.client.gui.GuiScreenBook$NextPageButton
+
+# Fields
+# <access modifier> <fully qualified class name> <field name>
+public net.minecraft.block.Block field_149764_J # blockMaterial
+
+# Methods
+# <access modifier> <fully qualified class name> <method name>(<parameter types>)<return type>
+public net.minecraft.block.Block func_149649_H()Lnet.minecraft.block.Block;  # disableStats