diff --git a/runelite-api/src/main/java/net/runelite/api/WorldType.java b/runelite-api/src/main/java/net/runelite/api/WorldType.java
index 81f2ae1d2d..851f3e6b28 100644
--- a/runelite-api/src/main/java/net/runelite/api/WorldType.java
+++ b/runelite-api/src/main/java/net/runelite/api/WorldType.java
@@ -76,7 +76,7 @@ public enum WorldType
 		this.mask = mask;
 	}
 
-	private static EnumSet<WorldType> PVP_WORLD_TYPES = EnumSet.of(
+	private static final EnumSet<WorldType> PVP_WORLD_TYPES = EnumSet.of(
 		DEADMAN,
 		PVP,
 		PVP_HIGH_RISK,