diff --git a/pom.xml b/pom.xml
index b276ad1..eefe7d0 100644
--- a/pom.xml
+++ b/pom.xml
@@ -8,8 +8,8 @@
     <version>UNOFFICIAL</version>
 
     <properties>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
+        <maven.compiler.source>17</maven.compiler.source>
+        <maven.compiler.target>17</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 
@@ -58,7 +58,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-shade-plugin</artifactId>
-                <version>3.2.4</version>
+                <version>3.3.0</version>
 
                 <configuration>
 
@@ -97,14 +97,14 @@
         <dependency>
             <groupId>org.spigotmc</groupId>
             <artifactId>spigot-api</artifactId>
-            <version>1.16.5-R0.1-SNAPSHOT</version>
+            <version>1.21.4-R0.1-SNAPSHOT</version>
             <scope>provided</scope>
         </dependency>
 
         <dependency>
             <groupId>com.github.TheBusyBiscuit</groupId>
             <artifactId>Slimefun4</artifactId>
-            <version>RC-27</version>
+            <version>experimental-SNAPSHOT</version>
             <scope>provided</scope>
             <exclusions>
                 <exclusion>
@@ -117,7 +117,7 @@
         <dependency>
             <groupId>org.bstats</groupId>
             <artifactId>bstats-bukkit</artifactId>
-            <version>2.2.1</version>
+            <version>3.1.0</version>
             <scope>compile</scope>
         </dependency>
     </dependencies>
diff --git a/src/main/java/io/github/thebusybiscuit/souljars/SoulJars.java b/src/main/java/io/github/thebusybiscuit/souljars/SoulJars.java
index a5af68d..32dc021 100644
--- a/src/main/java/io/github/thebusybiscuit/souljars/SoulJars.java
+++ b/src/main/java/io/github/thebusybiscuit/souljars/SoulJars.java
@@ -47,10 +47,10 @@ public void onEnable() {
         }
 
         emptyJar = new SlimefunItemStack("SOUL_JAR", JAR_TEXTURE, "&bSoul Jar &7(Empty)", "", "&rKill a Mob while having this", "&rItem in your Inventory to bind", "&rtheir Soul to this Jar");
-        itemGroup = new ItemGroup(new NamespacedKey(this, "soul_jars"), new CustomItemStack(emptyJar, "&bSoul Jars", "", "&a> Click to open"));
-        recipeType = new RecipeType(new NamespacedKey(this, "mob_killing"), new CustomItemStack(Material.DIAMOND_SWORD, "&cKill the specified Mob", "&cwhile having an empty Soul Jar", "&cin your Inventory"));
+        itemGroup = new ItemGroup(new NamespacedKey(this, "soul_jars"), CustomItemStack.create(emptyJar.item(), "&bSoul Jars", "", "&a> Click to open"));
+        recipeType = new RecipeType(new NamespacedKey(this, "mob_killing"), CustomItemStack.create(Material.DIAMOND_SWORD, "&cKill the specified Mob", "&cwhile having an empty Soul Jar", "&cin your Inventory"));
 
-        new SlimefunItem(itemGroup, emptyJar, RecipeType.ANCIENT_ALTAR, new ItemStack[] { SlimefunItems.EARTH_RUNE, new ItemStack(Material.SOUL_SAND), SlimefunItems.WATER_RUNE, new ItemStack(Material.SOUL_SAND), SlimefunItems.NECROTIC_SKULL, new ItemStack(Material.SOUL_SAND), SlimefunItems.AIR_RUNE, new ItemStack(Material.SOUL_SAND), SlimefunItems.FIRE_RUNE }, new CustomItemStack(emptyJar, 3)).register(this);
+        new SlimefunItem(itemGroup, emptyJar, RecipeType.ANCIENT_ALTAR, new ItemStack[] { SlimefunItems.EARTH_RUNE.item(), new ItemStack(Material.SOUL_SAND), SlimefunItems.WATER_RUNE.item(), new ItemStack(Material.SOUL_SAND), SlimefunItems.NECROTIC_SKULL.item(), new ItemStack(Material.SOUL_SAND), SlimefunItems.AIR_RUNE.item(), new ItemStack(Material.SOUL_SAND), SlimefunItems.FIRE_RUNE.item() }, CustomItemStack.create(emptyJar.item(), 3)).register(this);
         new JarsListener(this);
 
         for (String mob : cfg.getStringList("mobs")) {
@@ -80,19 +80,19 @@ private void registerSoul(EntityType type) {
         // @formatter:off
         SlimefunItemStack jarItem = new SlimefunItemStack(type.name() + "_SOUL_JAR", JAR_TEXTURE, "&cSoul Jar &7(" + name + ")", "", "&7Infused Souls: &e1");
         SlimefunItem jar = new UnplaceableBlock(itemGroup, jarItem, recipeType,
-        new ItemStack[] { null, null, null, emptyJar, null, new CustomItemStack(mobEgg, "&rKill " + souls + "x " + name), null, null, null });
+        new ItemStack[] { null, null, null, emptyJar.item(), null, CustomItemStack.create(mobEgg, "&rKill " + souls + "x " + name), null, null, null });
         jar.register(this);
 
         SlimefunItemStack filledJarItem = new SlimefunItemStack("FILLED_" + type.name() + "_SOUL_JAR", JAR_TEXTURE, "&cFilled Soul Jar &7(" + name + ")", "", "&7Infused Souls: &e" + souls);
         SlimefunItem filledJar = new FilledJar(itemGroup, filledJarItem, recipeType,
-        new ItemStack[] { null, null, null, emptyJar, null, new CustomItemStack(mobEgg, "&rKill " + souls + "x " + name), null, null, null });
+        new ItemStack[] { null, null, null, emptyJar.item(), null, CustomItemStack.create(mobEgg, "&rKill " + souls + "x " + name), null, null, null });
         filledJar.register(this);
 
         BrokenSpawner brokenSpawner = SlimefunItems.BROKEN_SPAWNER.getItem(BrokenSpawner.class);
 
         SlimefunItemStack spawnerItem = new SlimefunItemStack(type.toString() + "_BROKEN_SPAWNER", Material.SPAWNER, "&cBroken Spawner &7(" + name + ")");
         new SlimefunItem(itemGroup, spawnerItem, RecipeType.ANCIENT_ALTAR,
-        new ItemStack[] { new ItemStack(Material.IRON_BARS), SlimefunItems.EARTH_RUNE, new ItemStack(Material.IRON_BARS), SlimefunItems.EARTH_RUNE, filledJarItem, SlimefunItems.EARTH_RUNE, new ItemStack(Material.IRON_BARS), SlimefunItems.EARTH_RUNE, new ItemStack(Material.IRON_BARS) }, 
+        new ItemStack[] { new ItemStack(Material.IRON_BARS), SlimefunItems.EARTH_RUNE.item(), new ItemStack(Material.IRON_BARS), SlimefunItems.EARTH_RUNE.item(), filledJarItem.item(), SlimefunItems.EARTH_RUNE.item(), new ItemStack(Material.IRON_BARS), SlimefunItems.EARTH_RUNE.item(), new ItemStack(Material.IRON_BARS) }, 
         brokenSpawner.getItemForEntityType(type)).register(this);
         // @formatter:on
     }