diff --git a/tests/deck_builder/test_rules_engine.py b/tests/deck_builder/test_rules_engine.py
new file mode 100644
index 0000000..d3b417b
--- /dev/null
+++ b/tests/deck_builder/test_rules_engine.py
@@ -0,0 +1 @@
+# Tests for rules_engine — Phase 5