diff --git a/Main.py b/Main.py
index 715b0ace..007595de 100644
--- a/Main.py
+++ b/Main.py
@@ -261,7 +261,7 @@ def main(args, seed=None, fish=None):
             customize_shops(world, player)
     balance_money_progression(world)
 
-    if world.owShuffle[1] != 'vanilla' or world.owSwap[1] != 'vanilla':
+    if world.owShuffle[1] != 'vanilla' or world.owSwap[1] != 'vanilla' or world.seed.startsWith('M'):
         outfilebase = f'OR_{args.outputname if args.outputname else world.seed}'
     else:
         outfilebase = f'DR_{args.outputname if args.outputname else world.seed}'