mystery.diff

diff --git a/migrations/mysteryitems.js b/migrations/mysteryitems.js
index 4743757..be8c3b2 100644
--- a/migrations/mysteryitems.js
+++ b/migrations/mysteryitems.js
@@ -1,6 +1,6 @@
 var _id = '';
 var update = {
-  $push: {
+  $addToSet: {
     'purchased.plan.mysteryItems':{
       $each:['head_mystery_201412','armor_mystery_201412']
     }