diff --git a/fftcg/book.py b/fftcg/book.py
index 57ea116..070aa6d 100644
--- a/fftcg/book.py
+++ b/fftcg/book.py
@@ -15,7 +15,6 @@ class Book:
         # sort cards by element, then alphabetically
         cards.sort(key=lambda x: x.name)
         cards.sort(key=lambda x: "Multi" if len(x.elements) > 1 else x.elements[0])
-        self.__file_name = cards.file_name
 
         # all card face URLs
         urls = [f"https://fftcg.cdn.sewest.net/images/cards/full/{card.code}_{language}.jpg" for card in cards]
@@ -31,7 +30,7 @@ class Book:
 
         page_images: list[Image.Image]
         page_cards: Cards
-        for page_images, page_cards in zip(GRID.chunks(images), GRID.chunks(cards)):
+        for page_num, (page_images, page_cards) in enumerate(zip(GRID.chunks(images), GRID.chunks(cards))):
             # create book page Image
             page_image = Image.new("RGB", GRID * RESOLUTION)
             logger.info(f"New image: {page_image.size[0]}x{page_image.size[1]}")
@@ -49,6 +48,7 @@ class Book:
 
             # save page
             self.__pages.append({
+                "file_name": f"{cards.file_name}_{page_num}.jpg",
                 "image": page_image,
                 "cards": page_cards,
             })
@@ -56,9 +56,8 @@ class Book:
     def save(self) -> None:
         # save images
         for i, page in enumerate(self.__pages):
-            fn = f"{self.__file_name}_{i}.jpg"
             # save page image
-            page["image"].save(fn)
+            page["image"].save(page["file_name"])
 
         book: dict[str, Cards]
         try:
@@ -69,13 +68,12 @@ class Book:
 
         # save book
         for i, page in enumerate(self.__pages):
-            fn = f"{self.__file_name}_{i}.jpg"
             # ask for upload
-            face_url = input(f"Upload '{fn}' and paste URL: ")
+            face_url = input(f"Upload '{page['file_name']}' and paste URL: ")
             for card in page["cards"]:
                 card.face_url = face_url
             # add contents of that image
-            book[fn] = page["cards"]
+            book[page["file_name"]] = page["cards"]
 
         # update book.yml file
         with open(BOOK_YML_NAME, "w") as file:
diff --git a/fftcg/carddb.py b/fftcg/carddb.py
index 9e9805a..010b27b 100644
--- a/fftcg/carddb.py
+++ b/fftcg/carddb.py
@@ -41,7 +41,3 @@ class CardDB:
                 card.code: card
                 for card in cards
             }
-
-        # write carddb.yml file
-        with open("carddb.yml", "w") as file:
-            yaml.dump(self.__content, file, Dumper=yaml.Dumper)
diff --git a/fftcg/opus.py b/fftcg/opus.py
index 1cdaf0f..b3a8e11 100644
--- a/fftcg/opus.py
+++ b/fftcg/opus.py
@@ -73,7 +73,7 @@ class Opus(Cards):
 
             filters |= {
                 # light/darkness elemental deck
-                "Light/Darkness": lambda card: card.elements == ["Light"] or card.elements == ["Darkness"],
+                "Light-Darkness": lambda card: card.elements == ["Light"] or card.elements == ["Darkness"],
                 # multi element deck
                 "Multi": lambda card: len(card.elements) > 1,
             }
diff --git a/fftcg/ttsdeck.py b/fftcg/ttsdeck.py
index 2036257..5cf894a 100644
--- a/fftcg/ttsdeck.py
+++ b/fftcg/ttsdeck.py
@@ -11,36 +11,41 @@ class TTSDeck(Cards):
         super().__init__(name)
         self.__description = description
 
+        # get cards from carddb
         carddb = CardDB.get()
         self.extend([carddb[code] for code in codes])
 
-    def __str__(self) -> str:
-        face_urls = list(set([
+        # unique face urls used
+        unique_face_urls = set([
             card.face_url
             for card in self
-        ]))
+        ])
 
+        # lookup for indices of urls
+        self.__url_indices = {
+            url: i + 1
+            for i, url in enumerate(unique_face_urls)
+        }
+
+    @property
+    def tts_object(self) -> dict[str, any]:
+        # build the "CustomDeck" dictionary
         custom_deck = {
-            str(i + 1): {
+            str(i): {
                 "NumWidth": "10",
                 "NumHeight": "7",
                 "FaceURL": url,
                 "BackURL": CARD_BACK_URL,
-            } for i, url in enumerate(face_urls)
-        }
-
-        custom_deck_inv = {
-            url: i + 1
-            for i, url in enumerate(face_urls)
+            } for url, i in self.__url_indices.items()
         }
 
+        # values both in main deck and each contained card
         common_dict = {
             "Transform": {
                 "scaleX": 2.17822933,
                 "scaleY": 1.0,
                 "scaleZ": 2.17822933
             },
-
             "Locked": False,
             "Grid": True,
             "Snap": True,
@@ -50,40 +55,42 @@ class TTSDeck(Cards):
             "GridProjection": False,
         }
 
+        # cards contained in deck
         contained_objects = [
             {
-                "Name": "Card",
                 "Nickname": card.name,
                 "Description": card.text,
+                "CardID": 100 * self.__url_indices[card.face_url] + card.index,
 
-                "CardID": 100 * custom_deck_inv[card.face_url] + card.index,
-
+                "Name": "Card",
                 "Hands": True,
                 "SidewaysCard": False,
             } | common_dict for card in self
         ]
 
+        # extract the card ids
         deck_ids = [
             contained_object["CardID"]
             for contained_object in contained_objects
         ]
 
-        json_dict = {"ObjectStates": [
+        # create the deck dictionary
+        return {"ObjectStates": [
             {
-                "Name": "Deck",
                 "Nickname": self.name,
                 "Description": self.__description,
-
-                "Hands": False,
-                "SidewaysCard": False,
-
                 "DeckIDs": deck_ids,
                 "CustomDeck": custom_deck,
                 "ContainedObjects": contained_objects,
+
+                "Name": "Deck",
+                "Hands": False,
+                "SidewaysCard": False,
             } | common_dict
         ]}
 
-        return json.dumps(json_dict, indent=2)
-
-    def save(self, file_name: str) -> None:
-        pass
+    def save(self) -> None:
+        # only save if the deck contains cards
+        if self:
+            with open(f"{self.file_name}.json", "w") as file:
+                json.dump(self.tts_object, file, indent=2)
diff --git a/main.py b/main.py
index ab99cc4..ee97525 100755
--- a/main.py
+++ b/main.py
@@ -49,7 +49,7 @@ def main() -> None:
 
     # create elemental decks for opus
     for deck in opus.elemental_decks:
-        print(deck)
+        deck.save()
 
     # bye
     logging.info("Done. Put the generated JSON files in your 'Saved Objects' Folder.")