diff --git a/tests/mazes.cpp b/tests/mazes.cpp
index e202e82..031e3d1 100644
--- a/tests/mazes.cpp
+++ b/tests/mazes.cpp
@@ -174,6 +174,7 @@ TEST_CASE("hunt-and-kill scripting", "[mazes]") {
 
     if(valid) {
       REQUIRE(maze.validate() == true);
+      REQUIRE(map.INVARIANT() == true);
     }
 
     if(DUMP) maze.dump(valid ? "SCRIPTED" : "SCRIPTED FAIL!");