diff --git a/lib/CheckMap.hs b/lib/CheckMap.hs
index 2677a30c47fd66e7b7c6be6531ae00a6667328dd..04f3f75ae479bd837c53ddee52d173a1be666fd3 100644
--- a/lib/CheckMap.hs
+++ b/lib/CheckMap.hs
@@ -93,7 +93,7 @@ runLinter isMain config tiledmap depth = MapResult
   { mapresultLayer = invertThing layer
   , mapresultTileset = invertThing tileset
   , mapresultGeneral =
-    ([Hint Warning "main.json should link back to the lobby" | isMain && not (any linksLobby layerDeps)])
+    ([Hint Error "main.json should link back to the lobby" | isMain && not (any linksLobby layerDeps)])
     <> lintsToHints (resultToLints generalResult)
   , mapresultDepends = resultToDeps generalResult
     <> layerDeps