diff --git a/src/core/game/Game.ts b/src/core/game/Game.ts
index 8eec8c263..af5c05ec8 100644
--- a/src/core/game/Game.ts
+++ b/src/core/game/Game.ts
@@ -329,7 +329,11 @@ export interface Unit {
   troops(): number;
   owner(): Player;
   info(): UnitInfo;
-
+  data: {
+    pathCache?: Map<string, TileRef>;
+    [key: string]: any; 
+  };
+  
   // Location
   tile(): TileRef;
   lastTile(): TileRef;