delete them too

src/index.js

@@ -62,7 +62,6 @@ These are DESTRUCTIVE actions!
       return;
     }
 
-    this.log(`Modifying https://api.github.com/repos/${nwo} ...`);
     try {
       const data = { default_branch: "production" };
       const options = {
@@ -80,6 +79,22 @@ These are DESTRUCTIVE actions!
       return;
     }
 
+    try {
+      const { stdout } = await execa("git", ["branch", "-D", "master"]);
+      console.log(stdout);
+    } catch (error) {
+      this.error(error);
+      return;
+    }
+
+    try {
+      const { stdout } = await execa("git", ["push", "origin", ":master"]);
+      console.log(stdout);
+    } catch (error) {
+      this.error(error);
+      return;
+    }
+
     this.log(`All done! PS: GitHub, drop ICE 🤗`);
   }
 }