diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/ItemGroup.java b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/ItemGroup.java
index 4b4614e58..50ac90d1a 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/ItemGroup.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/ItemGroup.java
@@ -21,8 +21,8 @@ import org.bukkit.inventory.meta.ItemMeta;
 
 import io.github.thebusybiscuit.cscorelib2.item.CustomItem;
 import io.github.thebusybiscuit.slimefun4.api.SlimefunAddon;
-import io.github.thebusybiscuit.slimefun4.core.categories.LockedCategory;
-import io.github.thebusybiscuit.slimefun4.core.categories.SeasonalCategory;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.LockedItemGroup;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.SeasonalItemGroup;
 import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuide;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 
@@ -31,8 +31,8 @@ import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
  * 
  * @author TheBusyBiscuit
  *
- * @see LockedCategory
- * @see SeasonalCategory
+ * @see LockedItemGroup
+ * @see SeasonalItemGroup
  * 
  */
 public class ItemGroup implements Keyed {
@@ -205,7 +205,7 @@ public class ItemGroup implements Keyed {
                 name = item.getItemMeta().getDisplayName();
             }
 
-            if (this instanceof SeasonalCategory) {
+            if (this instanceof SeasonalItemGroup) {
                 meta.setDisplayName(ChatColor.GOLD + name);
             } else {
                 meta.setDisplayName(ChatColor.YELLOW + name);
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/FlexCategory.java b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/FlexItemGroup.java
similarity index 81%
rename from src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/FlexCategory.java
rename to src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/FlexItemGroup.java
index 0572f3c3f..07e973683 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/FlexCategory.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/FlexItemGroup.java
@@ -1,4 +1,4 @@
-package io.github.thebusybiscuit.slimefun4.core.categories;
+package io.github.thebusybiscuit.slimefun4.api.items.groups;
 
 import java.util.List;
 
@@ -16,7 +16,7 @@ import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuide;
 import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuideMode;
 
 /**
- * A {@link FlexCategory} is a {@link ItemGroup} inside the {@link SlimefunGuide} that can
+ * A {@link FlexItemGroup} is a {@link ItemGroup} inside the {@link SlimefunGuide} that can
  * be completely modified.
  * It cannot hold any {@link SlimefunItem} but can be completely overridden
  * to perform any action upon being opened.
@@ -24,20 +24,20 @@ import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuideMode;
  * @author TheBusyBiscuit
  *
  */
-public abstract class FlexCategory extends ItemGroup {
+public abstract class FlexItemGroup extends ItemGroup {
 
     @ParametersAreNonnullByDefault
-    protected FlexCategory(NamespacedKey key, ItemStack item) {
+    protected FlexItemGroup(NamespacedKey key, ItemStack item) {
         this(key, item, 3);
     }
 
     @ParametersAreNonnullByDefault
-    protected FlexCategory(NamespacedKey key, ItemStack item, int tier) {
+    protected FlexItemGroup(NamespacedKey key, ItemStack item, int tier) {
         super(key, item, tier);
     }
 
     /**
-     * This method returns whether this {@link FlexCategory} is visible under the given context.
+     * This method returns whether this {@link FlexItemGroup} is visible under the given context.
      * Implementing this method gives full flexibility over who can see the Category when and where.
      * 
      * @param p
@@ -45,20 +45,20 @@ public abstract class FlexCategory extends ItemGroup {
      * @param profile
      *            The {@link PlayerProfile} of the {@link Player}
      * @param layout
-     *            The {@link SlimefunGuideMode} in which this {@link FlexCategory} is viewed
+     *            The {@link SlimefunGuideMode} in which this {@link FlexItemGroup} is viewed
      * 
-     * @return Whether to display this {@link FlexCategory}
+     * @return Whether to display this {@link FlexItemGroup}
      */
     @ParametersAreNonnullByDefault
     public abstract boolean isVisible(Player p, PlayerProfile profile, SlimefunGuideMode layout);
 
     /**
-     * This method is called when a {@link Player} opens this {@link FlexCategory}.
+     * This method is called when a {@link Player} opens this {@link FlexItemGroup}.
      * This is an abstract method which needs to be implemented in order to determine what this
-     * {@link FlexCategory} should actually do as it cannot hold any items.
+     * {@link FlexItemGroup} should actually do as it cannot hold any items.
      * 
      * @param p
-     *            The {@link Player} who wants to open this {@link FlexCategory}
+     *            The {@link Player} who wants to open this {@link FlexItemGroup}
      * @param profile
      *            The corresponding {@link PlayerProfile} for that {@link Player}
      * @param layout
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/LockedCategory.java b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/LockedItemGroup.java
similarity index 91%
rename from src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/LockedCategory.java
rename to src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/LockedItemGroup.java
index d557a9b19..a7db69b04 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/LockedCategory.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/LockedItemGroup.java
@@ -1,4 +1,4 @@
-package io.github.thebusybiscuit.slimefun4.core.categories;
+package io.github.thebusybiscuit.slimefun4.api.items.groups;
 
 import java.util.ArrayList;
 import java.util.HashSet;
@@ -29,10 +29,10 @@ import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
  * @author TheBusyBiscuit
  * 
  * @see ItemGroup
- * @see SeasonalCategory
+ * @see SeasonalItemGroup
  * 
  */
-public class LockedCategory extends ItemGroup {
+public class LockedItemGroup extends ItemGroup {
 
     private final NamespacedKey[] keys;
     private final Set<ItemGroup> parents = new HashSet<>();
@@ -50,7 +50,7 @@ public class LockedCategory extends ItemGroup {
      * 
      */
     @ParametersAreNonnullByDefault
-    public LockedCategory(NamespacedKey key, ItemStack item, NamespacedKey... parents) {
+    public LockedItemGroup(NamespacedKey key, ItemStack item, NamespacedKey... parents) {
         this(key, item, 3, parents);
     }
 
@@ -68,7 +68,7 @@ public class LockedCategory extends ItemGroup {
      * 
      */
     @ParametersAreNonnullByDefault
-    public LockedCategory(NamespacedKey key, ItemStack item, int tier, NamespacedKey... parents) {
+    public LockedItemGroup(NamespacedKey key, ItemStack item, int tier, NamespacedKey... parents) {
         super(key, item, tier);
         Validate.noNullElements(parents, "A LockedCategory must not have any 'null' parents!");
 
@@ -99,7 +99,7 @@ public class LockedCategory extends ItemGroup {
     }
 
     /**
-     * Gets the list of parent categories for this {@link LockedCategory}.
+     * Gets the list of parent categories for this {@link LockedItemGroup}.
      * 
      * @return the list of parent categories
      * 
@@ -112,7 +112,7 @@ public class LockedCategory extends ItemGroup {
     }
 
     /**
-     * Adds a parent {@link ItemGroup} to this {@link LockedCategory}.
+     * Adds a parent {@link ItemGroup} to this {@link LockedItemGroup}.
      * 
      * @param category
      *            The {@link ItemGroup} to add as a parent
@@ -129,10 +129,10 @@ public class LockedCategory extends ItemGroup {
     }
 
     /**
-     * Removes a {@link ItemGroup} from the parents of this {@link LockedCategory}.
+     * Removes a {@link ItemGroup} from the parents of this {@link LockedItemGroup}.
      * 
      * @param category
-     *            The {@link ItemGroup} to remove from the parents of this {@link LockedCategory}
+     *            The {@link ItemGroup} to remove from the parents of this {@link LockedItemGroup}
      * 
      * @see #getParents()
      * @see #addParent(ItemGroup)
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/MultiCategory.java b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/NestedItemGroup.java
similarity index 73%
rename from src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/MultiCategory.java
rename to src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/NestedItemGroup.java
index f81f02beb..528baf5ef 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/MultiCategory.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/NestedItemGroup.java
@@ -1,4 +1,4 @@
-package io.github.thebusybiscuit.slimefun4.core.categories;
+package io.github.thebusybiscuit.slimefun4.api.items.groups;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -20,45 +20,46 @@ import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuideMode;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.implementation.guide.SurvivalSlimefunGuide;
 import io.github.thebusybiscuit.slimefun4.utils.ChestMenuUtils;
+
 import me.mrCookieSlime.CSCoreLibPlugin.general.Inventory.ChestMenu;
 
-public class MultiCategory extends FlexCategory {
+public class NestedItemGroup extends FlexItemGroup {
 
-    private static final int CATEGORY_SIZE = 36;
-    private final List<SubCategory> subCategories = new ArrayList<>();
+    private static final int GROUP_SIZE = 36;
+    private final List<SubItemGroup> subGroups = new ArrayList<>();
 
     @ParametersAreNonnullByDefault
-    public MultiCategory(NamespacedKey key, ItemStack item) {
+    public NestedItemGroup(NamespacedKey key, ItemStack item) {
         this(key, item, 3);
     }
 
     @ParametersAreNonnullByDefault
-    public MultiCategory(NamespacedKey key, ItemStack item, int tier) {
+    public NestedItemGroup(NamespacedKey key, ItemStack item, int tier) {
         super(key, item, tier);
     }
 
     /**
-     * This will add the given {@link SubCategory} to this {@link MultiCategory}.
+     * This will add the given {@link SubItemGroup} to this {@link NestedItemGroup}.
      * 
      * @param category
-     *            The {@link SubCategory} to add.
+     *            The {@link SubItemGroup} to add.
      */
-    public void addSubCategory(@Nonnull SubCategory category) {
-        Validate.notNull(category, "The Category cannot be null!");
+    public void addSubGroup(@Nonnull SubItemGroup category) {
+        Validate.notNull(category, "The sub item group cannot be null!");
 
-        subCategories.add(category);
+        subGroups.add(category);
     }
 
     /**
-     * This will remove the given {@link SubCategory} from this {@link MultiCategory} (if present).
+     * This will remove the given {@link SubItemGroup} from this {@link NestedItemGroup} (if present).
      * 
      * @param category
-     *            The {@link SubCategory} to remove.
+     *            The {@link SubItemGroup} to remove.
      */
-    public void removeSubCategory(@Nonnull SubCategory category) {
-        Validate.notNull(category, "The Category cannot be null!");
+    public void removeSubGroup(@Nonnull SubItemGroup category) {
+        Validate.notNull(category, "The sub item group cannot be null!");
 
-        subCategories.remove(category);
+        subGroups.remove(category);
     }
 
     @Override
@@ -96,12 +97,12 @@ public class MultiCategory extends FlexCategory {
 
         int index = 9;
 
-        int target = (CATEGORY_SIZE * (page - 1)) - 1;
+        int target = (GROUP_SIZE * (page - 1)) - 1;
 
-        while (target < (subCategories.size() - 1) && index < CATEGORY_SIZE + 9) {
+        while (target < (subGroups.size() - 1) && index < GROUP_SIZE + 9) {
             target++;
 
-            SubCategory category = subCategories.get(target);
+            SubItemGroup category = subGroups.get(target);
             menu.addItem(index, category.getItem(p));
             menu.addMenuClickHandler(index, (pl, slot, item, action) -> {
                 SlimefunGuide.openCategory(profile, category, mode, 1);
@@ -111,7 +112,7 @@ public class MultiCategory extends FlexCategory {
             index++;
         }
 
-        int pages = target == subCategories.size() - 1 ? page : (subCategories.size() - 1) / CATEGORY_SIZE + 1;
+        int pages = target == subGroups.size() - 1 ? page : (subGroups.size() - 1) / GROUP_SIZE + 1;
 
         menu.addItem(46, ChestMenuUtils.getPreviousButton(p, page, pages));
         menu.addMenuClickHandler(46, (pl, slot, item, action) -> {
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/SeasonalCategory.java b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/SeasonalItemGroup.java
similarity index 79%
rename from src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/SeasonalCategory.java
rename to src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/SeasonalItemGroup.java
index c8330101b..a4859a1d0 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/SeasonalCategory.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/SeasonalItemGroup.java
@@ -1,4 +1,4 @@
-package io.github.thebusybiscuit.slimefun4.core.categories;
+package io.github.thebusybiscuit.slimefun4.api.items.groups;
 
 import java.time.LocalDate;
 import java.time.Month;
@@ -20,14 +20,14 @@ import io.github.thebusybiscuit.slimefun4.api.items.ItemGroup;
  * @author TheBusyBiscuit
  * 
  * @see ItemGroup
- * @see LockedCategory
+ * @see LockedItemGroup
  */
-public class SeasonalCategory extends ItemGroup {
+public class SeasonalItemGroup extends ItemGroup {
 
     private final Month month;
 
     /**
-     * The constructor for a {@link SeasonalCategory}.
+     * The constructor for a {@link SeasonalItemGroup}.
      * 
      * @param key
      *            The {@link NamespacedKey} that is used to identify this {@link ItemGroup}
@@ -39,7 +39,7 @@ public class SeasonalCategory extends ItemGroup {
      *            The display item for this category
      */
     @ParametersAreNonnullByDefault
-    public SeasonalCategory(NamespacedKey key, Month month, int tier, ItemStack item) {
+    public SeasonalItemGroup(NamespacedKey key, Month month, int tier, ItemStack item) {
         super(key, item, tier);
         Validate.notNull(month, "The Month cannot be null");
 
@@ -47,9 +47,9 @@ public class SeasonalCategory extends ItemGroup {
     }
 
     /**
-     * This method returns the {@link Month} in which this {@link SeasonalCategory} will appear.
+     * This method returns the {@link Month} in which this {@link SeasonalItemGroup} will appear.
      * 
-     * @return the {@link Month} in which this {@link SeasonalCategory} appears
+     * @return the {@link Month} in which this {@link SeasonalItemGroup} appears
      */
     @Nonnull
     public Month getMonth() {
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/SubCategory.java b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/SubItemGroup.java
similarity index 68%
rename from src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/SubCategory.java
rename to src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/SubItemGroup.java
index 47eb2fb66..b8a3da78b 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/SubCategory.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/SubItemGroup.java
@@ -1,4 +1,4 @@
-package io.github.thebusybiscuit.slimefun4.core.categories;
+package io.github.thebusybiscuit.slimefun4.api.items.groups;
 
 import javax.annotation.Nonnull;
 import javax.annotation.ParametersAreNonnullByDefault;
@@ -12,31 +12,31 @@ import io.github.thebusybiscuit.slimefun4.api.SlimefunAddon;
 import io.github.thebusybiscuit.slimefun4.api.items.ItemGroup;
 
 /**
- * The {@link SubCategory} is a child {@link ItemGroup} of the
- * {@link MultiCategory}.
+ * The {@link SubItemGroup} is a child {@link ItemGroup} of the
+ * {@link NestedItemGroup}.
  * 
  * @author TheBusyBiscuit
  * 
- * @see MultiCategory
+ * @see NestedItemGroup
  *
  */
-public class SubCategory extends ItemGroup {
+public class SubItemGroup extends ItemGroup {
 
-    private final MultiCategory multiCategory;
+    private final NestedItemGroup multiCategory;
 
     @ParametersAreNonnullByDefault
-    public SubCategory(NamespacedKey key, MultiCategory parent, ItemStack item) {
+    public SubItemGroup(NamespacedKey key, NestedItemGroup parent, ItemStack item) {
         this(key, parent, item, 3);
     }
 
     @ParametersAreNonnullByDefault
-    public SubCategory(NamespacedKey key, MultiCategory parent, ItemStack item, int tier) {
+    public SubItemGroup(NamespacedKey key, NestedItemGroup parent, ItemStack item, int tier) {
         super(key, item, tier);
 
         Validate.notNull(parent, "The parent category cannot be null");
 
         multiCategory = parent;
-        parent.addSubCategory(this);
+        parent.addSubGroup(this);
     }
 
     @Override
@@ -49,7 +49,7 @@ public class SubCategory extends ItemGroup {
     }
 
     @Nonnull
-    public final MultiCategory getParent() {
+    public final NestedItemGroup getParent() {
         return multiCategory;
     }
 
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/package-info.java b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/package-info.java
new file mode 100644
index 000000000..e95ee138f
--- /dev/null
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/api/items/groups/package-info.java
@@ -0,0 +1,4 @@
+/**
+ * This package contains a few {@link io.github.thebusybiscuit.slimefun4.api.items.ItemGroup} variations.
+ */
+package io.github.thebusybiscuit.slimefun4.api.items.groups;
\ No newline at end of file
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/package-info.java b/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/package-info.java
deleted file mode 100644
index 2be27de3c..000000000
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/core/categories/package-info.java
+++ /dev/null
@@ -1,6 +0,0 @@
-/**
- * This package stores API classes that are centered around the extension of the
- * {@link me.mrCookieSlime.Slimefun.Objects.Category} class, such as
- * {@link io.github.thebusybiscuit.slimefun4.core.categories.SeasonalCategory} for example.
- */
-package io.github.thebusybiscuit.slimefun4.core.categories;
\ No newline at end of file
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/CheatSheetSlimefunGuide.java b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/CheatSheetSlimefunGuide.java
index 7f107d74b..04ec71b4c 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/CheatSheetSlimefunGuide.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/CheatSheetSlimefunGuide.java
@@ -13,8 +13,8 @@ import org.bukkit.inventory.Recipe;
 
 import io.github.thebusybiscuit.slimefun4.api.items.ItemGroup;
 import io.github.thebusybiscuit.slimefun4.api.items.SlimefunItem;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.FlexItemGroup;
 import io.github.thebusybiscuit.slimefun4.api.player.PlayerProfile;
-import io.github.thebusybiscuit.slimefun4.core.categories.FlexCategory;
 import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuideMode;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.utils.ChestMenuUtils;
@@ -53,7 +53,7 @@ public class CheatSheetSlimefunGuide extends SurvivalSlimefunGuide {
         List<ItemGroup> categories = new LinkedList<>();
 
         for (ItemGroup category : SlimefunPlugin.getRegistry().getCategories()) {
-            if (!(category instanceof FlexCategory)) {
+            if (!(category instanceof FlexItemGroup)) {
                 categories.add(category);
             }
         }
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/SurvivalSlimefunGuide.java b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/SurvivalSlimefunGuide.java
index 0872fedde..89164efcd 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/SurvivalSlimefunGuide.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/guide/SurvivalSlimefunGuide.java
@@ -31,10 +31,10 @@ import io.github.thebusybiscuit.cscorelib2.recipes.MinecraftRecipe;
 import io.github.thebusybiscuit.slimefun4.api.SlimefunAddon;
 import io.github.thebusybiscuit.slimefun4.api.items.ItemGroup;
 import io.github.thebusybiscuit.slimefun4.api.items.SlimefunItem;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.FlexItemGroup;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.LockedItemGroup;
 import io.github.thebusybiscuit.slimefun4.api.player.PlayerProfile;
 import io.github.thebusybiscuit.slimefun4.core.attributes.RecipeDisplayItem;
-import io.github.thebusybiscuit.slimefun4.core.categories.FlexCategory;
-import io.github.thebusybiscuit.slimefun4.core.categories.LockedCategory;
 import io.github.thebusybiscuit.slimefun4.core.guide.GuideHistory;
 import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuide;
 import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuideImplementation;
@@ -117,7 +117,7 @@ public class SurvivalSlimefunGuide implements SlimefunGuideImplementation {
 
         for (ItemGroup category : SlimefunPlugin.getRegistry().getCategories()) {
             try {
-                if (!category.isHidden(p) && (!(category instanceof FlexCategory) || ((FlexCategory) category).isVisible(p, profile, getMode()))) {
+                if (!category.isHidden(p) && (!(category instanceof FlexItemGroup) || ((FlexItemGroup) category).isVisible(p, profile, getMode()))) {
                     categories.add(category);
                 }
             } catch (Exception | LinkageError x) {
@@ -193,7 +193,7 @@ public class SurvivalSlimefunGuide implements SlimefunGuideImplementation {
     }
 
     private void displayCategory(ChestMenu menu, Player p, PlayerProfile profile, ItemGroup category, int index) {
-        if (!(category instanceof LockedCategory) || !isSurvivalMode() || ((LockedCategory) category).hasUnlocked(p, profile)) {
+        if (!(category instanceof LockedItemGroup) || !isSurvivalMode() || ((LockedItemGroup) category).hasUnlocked(p, profile)) {
             menu.addItem(index, category.getItem(p));
             menu.addMenuClickHandler(index, (pl, slot, item, action) -> {
                 openCategory(profile, category, 1);
@@ -209,7 +209,7 @@ public class SurvivalSlimefunGuide implements SlimefunGuideImplementation {
 
             lore.add("");
 
-            for (ItemGroup parent : ((LockedCategory) category).getParents()) {
+            for (ItemGroup parent : ((LockedItemGroup) category).getParents()) {
                 lore.add(parent.getItem(p).getItemMeta().getDisplayName());
             }
 
@@ -226,8 +226,8 @@ public class SurvivalSlimefunGuide implements SlimefunGuideImplementation {
             return;
         }
 
-        if (category instanceof FlexCategory) {
-            ((FlexCategory) category).open(p, profile, getMode());
+        if (category instanceof FlexItemGroup) {
+            ((FlexItemGroup) category).open(p, profile, getMode());
             return;
         }
 
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/magical/talismans/EnderTalisman.java b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/magical/talismans/EnderTalisman.java
index 738416b60..d9cc9db32 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/magical/talismans/EnderTalisman.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/items/magical/talismans/EnderTalisman.java
@@ -8,7 +8,7 @@ import org.bukkit.inventory.ItemStack;
 
 import io.github.thebusybiscuit.cscorelib2.item.CustomItem;
 import io.github.thebusybiscuit.slimefun4.api.items.SlimefunItemStack;
-import io.github.thebusybiscuit.slimefun4.core.categories.LockedCategory;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.LockedItemGroup;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunItems;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 
@@ -21,7 +21,7 @@ import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
  */
 class EnderTalisman extends Talisman {
 
-    private static final LockedCategory ENDER_TALISMANS_CATEGORY = new LockedCategory(new NamespacedKey(SlimefunPlugin.instance(), "ender_talismans"), new CustomItem(SlimefunItems.ENDER_TALISMAN, "&7Talismans - &aTier II"), 3, Talisman.TALISMANS_CATEGORY.getKey());
+    private static final LockedItemGroup ENDER_TALISMANS_CATEGORY = new LockedItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "ender_talismans"), new CustomItem(SlimefunItems.ENDER_TALISMAN, "&7Talismans - &aTier II"), 3, Talisman.TALISMANS_CATEGORY.getKey());
 
     @ParametersAreNonnullByDefault
     public EnderTalisman(Talisman parent, SlimefunItemStack item) {
diff --git a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/setup/DefaultCategories.java b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/setup/DefaultCategories.java
index 3c9518594..eb5eee65c 100644
--- a/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/setup/DefaultCategories.java
+++ b/src/main/java/io/github/thebusybiscuit/slimefun4/implementation/setup/DefaultCategories.java
@@ -7,8 +7,8 @@ import org.bukkit.NamespacedKey;
 
 import io.github.thebusybiscuit.cscorelib2.item.CustomItem;
 import io.github.thebusybiscuit.slimefun4.api.items.ItemGroup;
-import io.github.thebusybiscuit.slimefun4.core.categories.LockedCategory;
-import io.github.thebusybiscuit.slimefun4.core.categories.SeasonalCategory;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.LockedItemGroup;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.SeasonalItemGroup;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunItems;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
 import io.github.thebusybiscuit.slimefun4.utils.ChatUtils;
@@ -25,8 +25,8 @@ import io.github.thebusybiscuit.slimefun4.utils.SlimefunUtils;
  * @author TheBusyBiscuit
  * 
  * @see ItemGroup
- * @see LockedCategory
- * @see SeasonalCategory
+ * @see LockedItemGroup
+ * @see SeasonalItemGroup
  *
  */
 class DefaultCategories {
@@ -51,16 +51,16 @@ class DefaultCategories {
     protected final ItemGroup resources = new ItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "resources"), new CustomItem(SlimefunItems.SYNTHETIC_SAPPHIRE, "&7Resources"), 1);
 
     // Locked Categories
-    protected final LockedCategory electricity = new LockedCategory(new NamespacedKey(SlimefunPlugin.instance(), "electricity"), new CustomItem(SlimefunItems.NUCLEAR_REACTOR, "&bEnergy and Electricity"), 4, basicMachines.getKey());
-    protected final LockedCategory androids = new LockedCategory(new NamespacedKey(SlimefunPlugin.instance(), "androids"), new CustomItem(SlimefunItems.PROGRAMMABLE_ANDROID, "&cProgrammable Androids"), 4, basicMachines.getKey());
-    protected final ItemGroup cargo = new LockedCategory(new NamespacedKey(SlimefunPlugin.instance(), "cargo"), new CustomItem(SlimefunItems.CARGO_MANAGER, "&cCargo Management"), 4, basicMachines.getKey());
-    protected final LockedCategory gps = new LockedCategory(new NamespacedKey(SlimefunPlugin.instance(), "gps"), new CustomItem(SlimefunItems.GPS_TRANSMITTER, "&bGPS-based Machines"), 4, basicMachines.getKey());
+    protected final LockedItemGroup electricity = new LockedItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "electricity"), new CustomItem(SlimefunItems.NUCLEAR_REACTOR, "&bEnergy and Electricity"), 4, basicMachines.getKey());
+    protected final LockedItemGroup androids = new LockedItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "androids"), new CustomItem(SlimefunItems.PROGRAMMABLE_ANDROID, "&cProgrammable Androids"), 4, basicMachines.getKey());
+    protected final ItemGroup cargo = new LockedItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "cargo"), new CustomItem(SlimefunItems.CARGO_MANAGER, "&cCargo Management"), 4, basicMachines.getKey());
+    protected final LockedItemGroup gps = new LockedItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "gps"), new CustomItem(SlimefunItems.GPS_TRANSMITTER, "&bGPS-based Machines"), 4, basicMachines.getKey());
 
     // Seasonal Categories
-    protected final SeasonalCategory christmas = new SeasonalCategory(new NamespacedKey(SlimefunPlugin.instance(), "christmas"), Month.DECEMBER, 1, new CustomItem(SlimefunUtils.getCustomHead("215ba31cde2671b8f176de6a9ffd008035f0590d63ee240be6e8921cd2037a45"), ChatUtils.christmas("Christmas") + " &7(December only)"));
-    protected final SeasonalCategory valentinesDay = new SeasonalCategory(new NamespacedKey(SlimefunPlugin.instance(), "valentines_day"), Month.FEBRUARY, 2, new CustomItem(SlimefunUtils.getCustomHead("55d89431d14bfef2060461b4a3565614dc51115c001fae2508e8684bc0ae6a80"), "&dValentine's Day" + " &7(14th February)"));
-    protected final SeasonalCategory easter = new SeasonalCategory(new NamespacedKey(SlimefunPlugin.instance(), "easter"), Month.APRIL, 2, new CustomItem(HeadTexture.EASTER_EGG.getAsItemStack(), "&6Easter" + " &7(April)"));
-    protected final SeasonalCategory birthday = new SeasonalCategory(new NamespacedKey(SlimefunPlugin.instance(), "birthday"), Month.OCTOBER, 1, new CustomItem(Material.FIREWORK_ROCKET, "&a&lTheBusyBiscuit's Birthday &7(26th October)"));
-    protected final SeasonalCategory halloween = new SeasonalCategory(new NamespacedKey(SlimefunPlugin.instance(), "halloween"), Month.OCTOBER, 1, new CustomItem(Material.JACK_O_LANTERN, "&6&lHalloween &7(31st October)"));
+    protected final SeasonalItemGroup christmas = new SeasonalItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "christmas"), Month.DECEMBER, 1, new CustomItem(SlimefunUtils.getCustomHead("215ba31cde2671b8f176de6a9ffd008035f0590d63ee240be6e8921cd2037a45"), ChatUtils.christmas("Christmas") + " &7(December only)"));
+    protected final SeasonalItemGroup valentinesDay = new SeasonalItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "valentines_day"), Month.FEBRUARY, 2, new CustomItem(SlimefunUtils.getCustomHead("55d89431d14bfef2060461b4a3565614dc51115c001fae2508e8684bc0ae6a80"), "&dValentine's Day" + " &7(14th February)"));
+    protected final SeasonalItemGroup easter = new SeasonalItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "easter"), Month.APRIL, 2, new CustomItem(HeadTexture.EASTER_EGG.getAsItemStack(), "&6Easter" + " &7(April)"));
+    protected final SeasonalItemGroup birthday = new SeasonalItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "birthday"), Month.OCTOBER, 1, new CustomItem(Material.FIREWORK_ROCKET, "&a&lTheBusyBiscuit's Birthday &7(26th October)"));
+    protected final SeasonalItemGroup halloween = new SeasonalItemGroup(new NamespacedKey(SlimefunPlugin.instance(), "halloween"), Month.OCTOBER, 1, new CustomItem(Material.JACK_O_LANTERN, "&6&lHalloween &7(31st October)"));
 
 }
diff --git a/src/test/java/io/github/thebusybiscuit/slimefun4/implementation/registration/TestCategories.java b/src/test/java/io/github/thebusybiscuit/slimefun4/implementation/registration/TestCategories.java
index 551fc6834..6710a4e48 100644
--- a/src/test/java/io/github/thebusybiscuit/slimefun4/implementation/registration/TestCategories.java
+++ b/src/test/java/io/github/thebusybiscuit/slimefun4/implementation/registration/TestCategories.java
@@ -17,10 +17,10 @@ import io.github.thebusybiscuit.cscorelib2.item.CustomItem;
 import io.github.thebusybiscuit.slimefun4.api.items.ItemGroup;
 import io.github.thebusybiscuit.slimefun4.api.items.SlimefunItem;
 import io.github.thebusybiscuit.slimefun4.api.items.SlimefunItemStack;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.FlexItemGroup;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.LockedItemGroup;
+import io.github.thebusybiscuit.slimefun4.api.items.groups.SeasonalItemGroup;
 import io.github.thebusybiscuit.slimefun4.api.player.PlayerProfile;
-import io.github.thebusybiscuit.slimefun4.core.categories.FlexCategory;
-import io.github.thebusybiscuit.slimefun4.core.categories.LockedCategory;
-import io.github.thebusybiscuit.slimefun4.core.categories.SeasonalCategory;
 import io.github.thebusybiscuit.slimefun4.core.guide.SlimefunGuideMode;
 import io.github.thebusybiscuit.slimefun4.core.researching.Research;
 import io.github.thebusybiscuit.slimefun4.implementation.SlimefunPlugin;
@@ -130,14 +130,14 @@ class TestCategories {
     @Test
     @DisplayName("Test LockedCategory parental locking")
     void testLockedCategoriesParents() {
-        Assertions.assertThrows(IllegalArgumentException.class, () -> new LockedCategory(new NamespacedKey(plugin, "locked"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), (NamespacedKey) null));
+        Assertions.assertThrows(IllegalArgumentException.class, () -> new LockedItemGroup(new NamespacedKey(plugin, "locked"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), (NamespacedKey) null));
 
         ItemGroup category = new ItemGroup(new NamespacedKey(plugin, "unlocked"), new CustomItem(Material.EMERALD, "&5I am SHERlocked"));
         category.register(plugin);
 
         ItemGroup unregistered = new ItemGroup(new NamespacedKey(plugin, "unregistered"), new CustomItem(Material.EMERALD, "&5I am unregistered"));
 
-        LockedCategory locked = new LockedCategory(new NamespacedKey(plugin, "locked"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), category.getKey(), unregistered.getKey());
+        LockedItemGroup locked = new LockedItemGroup(new NamespacedKey(plugin, "locked"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), category.getKey(), unregistered.getKey());
         locked.register(plugin);
 
         Assertions.assertTrue(locked.getParents().contains(category));
@@ -159,12 +159,12 @@ class TestCategories {
         Player player = server.addPlayer();
         PlayerProfile profile = TestUtilities.awaitProfile(player);
 
-        Assertions.assertThrows(IllegalArgumentException.class, () -> new LockedCategory(new NamespacedKey(plugin, "locked"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), (NamespacedKey) null));
+        Assertions.assertThrows(IllegalArgumentException.class, () -> new LockedItemGroup(new NamespacedKey(plugin, "locked"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), (NamespacedKey) null));
 
         ItemGroup category = new ItemGroup(new NamespacedKey(plugin, "parent"), new CustomItem(Material.EMERALD, "&5I am SHERlocked"));
         category.register(plugin);
 
-        LockedCategory locked = new LockedCategory(new NamespacedKey(plugin, "locked2"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), category.getKey());
+        LockedItemGroup locked = new LockedItemGroup(new NamespacedKey(plugin, "locked2"), new CustomItem(Material.GOLD_NUGGET, "&6Locked Test"), category.getKey());
         locked.register(plugin);
 
         // No Items, so it should be unlocked
@@ -192,7 +192,7 @@ class TestCategories {
     void testSeasonalCategories() {
         // Category with current Month
         Month month = LocalDate.now().getMonth();
-        SeasonalCategory category = new SeasonalCategory(new NamespacedKey(plugin, "seasonal"), month, 1, new CustomItem(Material.NETHER_STAR, "&cSeasonal Test"));
+        SeasonalItemGroup category = new SeasonalItemGroup(new NamespacedKey(plugin, "seasonal"), month, 1, new CustomItem(Material.NETHER_STAR, "&cSeasonal Test"));
         SlimefunItem item = TestUtilities.mockSlimefunItem(plugin, "SEASONAL_ITEM", new CustomItem(Material.NETHER_STAR, "&dSeasonal Test Star"));
         item.setCategory(category);
         item.register(plugin);
@@ -204,14 +204,14 @@ class TestCategories {
         Assertions.assertFalse(category.isHidden(player));
 
         // Category with future Month
-        SeasonalCategory category2 = new SeasonalCategory(category.getKey(), month.plus(6), 1, new CustomItem(Material.MILK_BUCKET, "&dSeasonal Test"));
+        SeasonalItemGroup category2 = new SeasonalItemGroup(category.getKey(), month.plus(6), 1, new CustomItem(Material.MILK_BUCKET, "&dSeasonal Test"));
         Assertions.assertTrue(category2.isHidden(player));
     }
 
     @Test
     @DisplayName("Test the FlexCategory")
     void testFlexCategory() {
-        FlexCategory category = new FlexCategory(new NamespacedKey(plugin, "flex"), new CustomItem(Material.REDSTONE, "&4Weird flex but ok")) {
+        FlexItemGroup category = new FlexItemGroup(new NamespacedKey(plugin, "flex"), new CustomItem(Material.REDSTONE, "&4Weird flex but ok")) {
 
             @Override
             public void open(Player p, PlayerProfile profile, SlimefunGuideMode layout) {