diff --git a/magic_spoiler/__main__.py b/magic_spoiler/__main__.py
index a86b152e..ba49f6f9 100644
--- a/magic_spoiler/__main__.py
+++ b/magic_spoiler/__main__.py
@@ -194,6 +194,8 @@ def open_header(card_xml_file: IO[Any]) -> None:
         + "  <!--\n"
         + "  Created At: " + datetime.datetime.utcnow().strftime("%a, %b %d %Y, %H:%M:%S") + " (UTC)\n"
         + "  Created By: Magic-Spoiler project @ https://github.com/Cockatrice/Magic-Spoiler\n"
+        + "  \n"
+        + "  THIS FILE IS AUTOMATICALLY GENERATED & ALL EDITS WILL BE DISCARDED.\n"
         + "  -->\n"
         + "<sets>\n"
     )