diff --git a/build.gradle b/build.gradle
index e45243f..e466134 100644
--- a/build.gradle
+++ b/build.gradle
@@ -17,7 +17,7 @@ preprocess {
 	def mc1204 = createNode('1.20.4', 1_20_04, 'yarn')
 	def mc1205 = createNode('1.20.5', 1_20_05, 'yarn')
 	def mc1206 = createNode('1.20.6', 1_20_06, 'yarn')
-	def mc121 = createNode('1.21', 1_20_00, 'yarn')
+	def mc121 = createNode('1.21', 1_21_00, 'yarn')
 	def mc1211 = createNode('1.21.1', 1_21_01, 'yarn')
 
 	mc116.link(mc117, file('versions/mapping-1.16-1.17.txt'))