diff --git a/RULES.txt b/RULES.txt
index 785aabb..e2853ef 100644
--- a/RULES.txt
+++ b/RULES.txt
@@ -1,3 +1,4 @@
+- https://www.looneylabs.com/rules/martian-chess
 - [ ] Movement
     - [ ] Pawn movement
     - [ ] Drone movement