diff --git a/massgen.py b/massgen.py
index f12c8e0..8bb7160 100644
--- a/massgen.py
+++ b/massgen.py
@@ -9,6 +9,7 @@ for series in massdecks:
         if card[:-2] in massdecks[series]:
             ownedlist.append(card)
     if len(ownedlist) > 0:
+        ownedlist = sorted(list(dict.fromkeys(ownedlist)))
         massowned[series] = ownedlist
 
 def massindexgen():