diff --git a/src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BCLBiomeBuilder.java b/src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BCLBiomeBuilder.java
index d61b9f43..0ff99334 100644
--- a/src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BCLBiomeBuilder.java
+++ b/src/main/java/org/betterx/bclib/api/v2/levelgen/biomes/BCLBiomeBuilder.java
@@ -861,7 +861,7 @@ public class BCLBiomeBuilder {
      * @return same {@link BCLBiomeBuilder} instance.
      */
     public BCLBiomeBuilder vertical() {
-        this.vertical = vertical;
+        this.vertical = true;
         return this;
     }