Fixed price mixed up.

include/constants/item_config.h

@@ -16,7 +16,7 @@
 // Item config
 #define I_SHINY_CHARM_REROLLS   3       // Amount of re-rolls if the player has the Shiny Charm. Set to 0 to disable Shiny Charm's effects.
 #define I_KEY_FOSSILS           GEN_7   // In Gen4+, all Gen 3 fossils became regular items.
-#define I_KEY_ESCAPE_ROPE       GEN_7   // In Gen8, Escape Rope became a Key Item.
+#define I_KEY_ESCAPE_ROPE       GEN_7   // In Gen8, Escape Rope became a Key Item. Keep in mind, this will make it free to buy in marts.
 
 // Ball config
 #define I_LURE_BALL_MODIFIER    GEN_7   // In Gen7+, Lure Ball's catch multiplier is x5 instead of x3.

src/data/items.h

@@ -1281,12 +1281,13 @@ const struct Item gItems[] =
     {
         .name = _("Escape Rope"),
         .itemId = ITEM_ESCAPE_ROPE,
-        .price = 550,
         .description = sEscapeRopeDesc,
         #if I_KEY_ESCAPE_ROPE >= GEN_8
+        .price = 0,
         .importance = 1,
         .pocket = POCKET_KEY_ITEMS,
         #else
+        .price = 550,
         .importance = 0,
         .pocket = POCKET_ITEMS,
         #endif