diff --git a/src/main/java/com/falsepattern/endlessids/mixin/mixins/common/twilightforest/TFBiomeBaseMixin.java b/src/main/java/com/falsepattern/endlessids/mixin/mixins/common/twilightforest/TFBiomeBaseMixin.java
new file mode 100644
index 0000000..8b80043
--- /dev/null
+++ b/src/main/java/com/falsepattern/endlessids/mixin/mixins/common/twilightforest/TFBiomeBaseMixin.java
@@ -0,0 +1,19 @@
+package com.falsepattern.endlessids.mixin.mixins.common.twilightforest;
+
+import com.falsepattern.endlessids.constants.ExtendedConstants;
+import com.falsepattern.endlessids.constants.VanillaConstants;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.Constant;
+import org.spongepowered.asm.mixin.injection.ModifyConstant;
+import twilightforest.biomes.TFBiomeBase;
+
+@Mixin(value = TFBiomeBase.class,
+       remap = false)
+public abstract class TFBiomeBaseMixin {
+    @ModifyConstant(method = "findNextOpenBiomeId",
+                    constant = @Constant(intValue = VanillaConstants.biomeIDCount),
+                    require = 1)
+    private static int extendIDs(int constant) {
+        return ExtendedConstants.biomeIDCount;
+    }
+}
diff --git a/src/main/java/com/falsepattern/endlessids/mixin/plugin/Mixin.java b/src/main/java/com/falsepattern/endlessids/mixin/plugin/Mixin.java
index 303374a..cc35cfb 100644
--- a/src/main/java/com/falsepattern/endlessids/mixin/plugin/Mixin.java
+++ b/src/main/java/com/falsepattern/endlessids/mixin/plugin/Mixin.java
@@ -120,6 +120,7 @@ public enum Mixin implements IMixin {
     //region TwilightForest->common
     ChunkProviderTwilightForestMixin(Side.COMMON, require(TargetedMod.TWILIGHTFOREST),
                                      "twilightforest.ChunkProviderTwilightForestMixin"),
+    TFBiomeBaseMixin(Side.COMMON, require(TargetedMod.TWILIGHTFOREST), "twilightforest.TFBiomeBaseMixin"),
     //endregion TwilightForest->common
     //region UBC->common
     UBCOreUBifierMixin(Side.COMMON, require(TargetedMod.UBC), "ubc.OreUBifierMixin"),