diff --git a/patches/api/Add-FeatureFlag-API.patch b/patches/api/Add-FeatureFlag-API.patch
index e37e1a72f0..eb23dbdc9f 100644
--- a/patches/api/Add-FeatureFlag-API.patch
+++ b/patches/api/Add-FeatureFlag-API.patch
@@ -116,10 +116,11 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  import org.jetbrains.annotations.ApiStatus;
  
  /**
-  * This represents a Feature Flag for a World.
+- * This represents a Feature Flag for a World.
 - * <br>
 - * Flags which are unavailable in the current version will be null and/or
 - * removed.
++ * This represents a Feature Flag for a {@link io.papermc.paper.world.flag.FeatureFlagSetHolder}.
   */
 -@ApiStatus.Experimental
  public interface FeatureFlag extends Keyed {
@@ -253,6 +254,16 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  
      /**
       * Typed represents a subtype of {@link BlockType}s that have a known block
+@@ -0,0 +0,0 @@ public interface BlockType extends Keyed, Translatable, net.kyori.adventure.tran
+      *
+      * @param world the world to check
+      * @return true if this BlockType can be used in this World.
++     * @deprecated Use {@link io.papermc.paper.world.flag.FeatureFlagSetHolder#isEnabled(io.papermc.paper.world.flag.FeatureDependant)}
+      */
++    @Deprecated(forRemoval = true, since = "1.21.1") // Paper
+     boolean isEnabledByFeature(@NotNull World world);
+ 
+     /**
 diff --git a/src/main/java/org/bukkit/entity/EntityType.java b/src/main/java/org/bukkit/entity/EntityType.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/entity/EntityType.java
@@ -292,6 +303,16 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  
      /**
       * Typed represents a subtype of {@link ItemType}s that have a known item meta type
+@@ -0,0 +0,0 @@ public interface ItemType extends Keyed, Translatable, net.kyori.adventure.trans
+      *
+      * @param world the world to check
+      * @return true if this ItemType can be used in this World.
++     * @deprecated use {@link io.papermc.paper.world.flag.FeatureFlagSetHolder#isEnabled(io.papermc.paper.world.flag.FeatureDependant)}
+      */
++    @Deprecated(forRemoval = true, since = "1.21.1") // Paper
+     boolean isEnabledByFeature(@NotNull World world);
+ 
+     /**
 diff --git a/src/main/java/org/bukkit/potion/PotionEffectType.java b/src/main/java/org/bukkit/potion/PotionEffectType.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/potion/PotionEffectType.java