diff --git a/patches/api/0487-Add-FeatureFlag-API.patch b/patches/api/0487-Add-FeatureFlag-API.patch
index 946c294f8c..9ac403aad4 100644
--- a/patches/api/0487-Add-FeatureFlag-API.patch
+++ b/patches/api/0487-Add-FeatureFlag-API.patch
@@ -100,7 +100,7 @@ index 0000000000000000000000000000000000000000..c4432ee20872eeb127852159cf89ed00
 +    @Unmodifiable @NonNull Set<FeatureFlag> getFeatureFlags();
 +}
 diff --git a/src/main/java/org/bukkit/FeatureFlag.java b/src/main/java/org/bukkit/FeatureFlag.java
-index 026b1832bcd163ab89668c991bf002e608e36aef..8fab13dc12c8fd6181479ab6e31e2498a8a91ee5 100644
+index 026b1832bcd163ab89668c991bf002e608e36aef..b5e87480b6a1d064547e4e608f3d402825931a00 100644
 --- a/src/main/java/org/bukkit/FeatureFlag.java
 +++ b/src/main/java/org/bukkit/FeatureFlag.java
 @@ -1,37 +1,56 @@
@@ -116,10 +116,11 @@ index 026b1832bcd163ab89668c991bf002e608e36aef..8fab13dc12c8fd6181479ab6e31e2498
  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 {
@@ -241,7 +242,7 @@ index 330e3013eda204aa9b33d5e1c3104e0b595abdbc..c80e0ef587a001ee6de3f5c182cc9696
      /**
       * Do not use, method will get removed, and the plugin won't run
 diff --git a/src/main/java/org/bukkit/block/BlockType.java b/src/main/java/org/bukkit/block/BlockType.java
-index 8f430a4067fc722ebfbca846cccded4fb0a3a4e5..4aa79016eb5f7edf930c82d30ff25078fdb88436 100644
+index 8f430a4067fc722ebfbca846cccded4fb0a3a4e5..a98cc1bc25fcde49b525ae6f841ea2841111e028 100644
 --- a/src/main/java/org/bukkit/block/BlockType.java
 +++ b/src/main/java/org/bukkit/block/BlockType.java
 @@ -123,7 +123,7 @@ import org.jetbrains.annotations.Nullable;
@@ -253,6 +254,16 @@ index 8f430a4067fc722ebfbca846cccded4fb0a3a4e5..4aa79016eb5f7edf930c82d30ff25078
  
      /**
       * Typed represents a subtype of {@link BlockType}s that have a known block
+@@ -3479,7 +3479,9 @@ 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 ba605ad75d4ed920c0dc4527529998041a58676b..a78e1c431a6ea46ba7c44880e25a871f473bef41 100644
 --- a/src/main/java/org/bukkit/entity/EntityType.java
@@ -280,7 +291,7 @@ index 5067f1371433cccd3287af7f03e152f2c3c1ece3..e0cb282541548ac3bd24cce86b3413f5
      /**
       * Gets the unique name of this world
 diff --git a/src/main/java/org/bukkit/inventory/ItemType.java b/src/main/java/org/bukkit/inventory/ItemType.java
-index 0168f0a14a3e899e84c5e36963ff79950ab580fb..86887e8b20288b8204adcc64993b39f94269a0eb 100644
+index 0168f0a14a3e899e84c5e36963ff79950ab580fb..5b4449f63595193efcd1329b9df0558cfaa2c7b2 100644
 --- a/src/main/java/org/bukkit/inventory/ItemType.java
 +++ b/src/main/java/org/bukkit/inventory/ItemType.java
 @@ -48,7 +48,7 @@ import org.jetbrains.annotations.Nullable;
@@ -292,6 +303,16 @@ index 0168f0a14a3e899e84c5e36963ff79950ab580fb..86887e8b20288b8204adcc64993b39f9
  
      /**
       * Typed represents a subtype of {@link ItemType}s that have a known item meta type
+@@ -2306,7 +2306,9 @@ 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 10fa51d116b40450b51af9110d5637f3505ebf65..647452f16e4bf7e5a61520123e62d9408ec9adfb 100644
 --- a/src/main/java/org/bukkit/potion/PotionEffectType.java