diff --git a/core/adb_handlers/__init__.py b/core/adb_handlers/__init__.py
index 0c96baf..9a8121f 100644
--- a/core/adb_handlers/__init__.py
+++ b/core/adb_handlers/__init__.py
@@ -2,5 +2,5 @@ from .base import ADBBaseRequest, ADBBaseResponse, ADBHeader, ADBHeaderException
 from .base import CompanyCodes, ReaderFwVer, CMD_CODE_GOODBYE, HEADER_SIZE
 from .lookup import ADBLookupRequest, ADBLookupResponse, ADBLookupExResponse
 from .campaign import ADBCampaignClearRequest, ADBCampaignClearResponse, ADBCampaignResponse, ADBOldCampaignRequest, ADBOldCampaignResponse
-from .felica import ADBFelicaLookupRequest, ADBFelicaLookupResponse, ADBFelicaLookup2Request, ADBFelicaLookup2Response
+from .felica import ADBFelicaLookupRequest, ADBFelicaLookupResponse, ADBFelicaLookupExRequest, ADBFelicaLookupExResponse
 from .log import ADBLogExRequest, ADBLogRequest, ADBStatusLogRequest, ADBLogExResponse
diff --git a/core/adb_handlers/felica.py b/core/adb_handlers/felica.py
index 22c9f05..b7fdc2e 100644
--- a/core/adb_handlers/felica.py
+++ b/core/adb_handlers/felica.py
@@ -35,7 +35,7 @@ class ADBFelicaLookupResponse(ADBBaseResponse):
 
         return self.head.make() + resp_struct
 
-class ADBFelicaLookup2Request(ADBBaseRequest):
+class ADBFelicaLookupExRequest(ADBBaseRequest):
     def __init__(self, data: bytes) -> None:
         super().__init__(data)
         self.random = struct.unpack_from("<16s", data, 0x20)[0]
@@ -46,7 +46,7 @@ class ADBFelicaLookup2Request(ADBBaseRequest):
         self.company = CompanyCodes(int.from_bytes(company, 'little'))
         self.fw_ver = ReaderFwVer.from_byte(fw_ver)
 
-class ADBFelicaLookup2Response(ADBBaseResponse):
+class ADBFelicaLookupExResponse(ADBBaseResponse):
     def __init__(self, user_id: Union[int, None] = None, access_code: Union[str, None] = None, game_id: str = "SXXX", store_id: int = 1, keychip_id: str = "A69E01A8888", code: int = 0x12, length: int = 0x130, status: int = 1) -> None:
         super().__init__(code, length, status, game_id, store_id, keychip_id)
         self.user_id = user_id if user_id is not None else -1
@@ -56,7 +56,7 @@ class ADBFelicaLookup2Response(ADBBaseResponse):
         self.auth_key = [0] * 256
 
     @classmethod
-    def from_req(cls, req: ADBHeader, user_id: Union[int, None] = None, access_code: Union[str, None] = None) -> "ADBFelicaLookup2Response":
+    def from_req(cls, req: ADBHeader, user_id: Union[int, None] = None, access_code: Union[str, None] = None) -> "ADBFelicaLookupExResponse":
         c = cls(user_id, access_code, req.game_id, req.store_id, req.keychip_id)
         c.head.protocol_ver = req.protocol_ver
         return c
diff --git a/core/aimedb.py b/core/aimedb.py
index 88796c7..6d5bd57 100644
--- a/core/aimedb.py
+++ b/core/aimedb.py
@@ -176,6 +176,12 @@ class AimedbServlette():
 
     async def handle_lookup(self, data: bytes, resp_code: int) -> ADBBaseResponse:
         req = ADBLookupRequest(data)
+        if req.access_code == "00000000000000000000":
+            self.logger.warn(f"All-zero access code from {req.head.keychip_id}")
+            ret = ADBLookupResponse.from_req(req.head, -1)
+            ret.head.status = ADBStatus.BAN_SYS
+            return ret
+        
         user_id = await self.data.card.get_user_id_from_card(req.access_code)
         is_banned = await self.data.card.get_card_banned(req.access_code)
         is_locked = await self.data.card.get_card_locked(req.access_code)
@@ -201,6 +207,12 @@ class AimedbServlette():
 
     async def handle_lookup_ex(self, data: bytes, resp_code: int) -> ADBBaseResponse:
         req = ADBLookupRequest(data)
+        if req.access_code == "00000000000000000000":
+            self.logger.warn(f"All-zero access code from {req.head.keychip_id}")
+            ret = ADBLookupExResponse.from_req(req.head, -1)
+            ret.head.status = ADBStatus.BAN_SYS
+            return ret
+        
         user_id = await self.data.card.get_user_id_from_card(req.access_code)
 
         is_banned = await self.data.card.get_card_banned(req.access_code)
@@ -241,6 +253,12 @@ class AimedbServlette():
         """
         req = ADBFelicaLookupRequest(data)
         idm = req.idm.zfill(16)
+        if idm == "0000000000000000":
+            self.logger.warn(f"All-zero IDm from {req.head.keychip_id}")
+            ret = ADBFelicaLookupResponse.from_req(req.head, "00000000000000000000")
+            ret.head.status = ADBStatus.BAN_SYS
+            return ret
+
         card = await self.data.card.get_card_by_idm(idm)
         if not card:
             ac = self.data.card.to_access_code(idm)
@@ -262,6 +280,14 @@ class AimedbServlette():
         because we don't implement felica_lookup properly.
         """
         req = ADBFelicaLookupRequest(data)
+        idm = req.idm.zfill(16)
+        
+        if idm == "0000000000000000":
+            self.logger.warn(f"All-zero IDm from {req.head.keychip_id}")
+            ret = ADBFelicaLookupResponse.from_req(req.head, "00000000000000000000")
+            ret.head.status = ADBStatus.BAN_SYS
+            return ret
+        
         ac = self.data.card.to_access_code(req.idm)
         
         if self.config.server.allow_user_registration:
@@ -292,9 +318,16 @@ class AimedbServlette():
         return ADBFelicaLookupResponse.from_req(req.head, ac)
 
     async def handle_felica_lookup_ex(self, data: bytes, resp_code: int) -> bytes:
-        req = ADBFelicaLookup2Request(data)
+        req = ADBFelicaLookupExRequest(data)
         user_id = None
         idm = req.idm.zfill(16)
+        
+        if idm == "0000000000000000":
+            self.logger.warn(f"All-zero IDm from {req.head.keychip_id}")
+            ret = ADBFelicaLookupExResponse.from_req(req.head, -1, "00000000000000000000")
+            ret.head.status = ADBStatus.BAN_SYS
+            return ret
+        
         card = await self.data.card.get_card_by_idm(idm)
         if not card:
             access_code = self.data.card.to_access_code(idm)
@@ -314,7 +347,7 @@ class AimedbServlette():
             f"idm {idm} ipm {req.pmm} -> access_code {access_code} user_id {user_id}"
         )
 
-        resp = ADBFelicaLookup2Response.from_req(req.head, user_id, access_code)
+        resp = ADBFelicaLookupExResponse.from_req(req.head, user_id, access_code)
         
         if user_id > 0:
             if card['is_banned'] and card['is_locked']:
@@ -347,6 +380,12 @@ class AimedbServlette():
     async def handle_register(self, data: bytes, resp_code: int) -> bytes:
         req = ADBLookupRequest(data)
         user_id = -1
+        
+        if req.access_code == "00000000000000000000":
+            self.logger.warn(f"All-zero access code from {req.head.keychip_id}")
+            ret = ADBLookupResponse.from_req(req.head, -1)
+            ret.head.status = ADBStatus.BAN_SYS
+            return ret
 
         if self.config.server.allow_user_registration:
             user_id = await self.data.user.create_user()
diff --git a/titles/chuni/const.py b/titles/chuni/const.py
index d037842..003c618 100644
--- a/titles/chuni/const.py
+++ b/titles/chuni/const.py
@@ -19,11 +19,13 @@ class ChuniConstants:
     VER_CHUNITHM_CRYSTAL = 8
     VER_CHUNITHM_CRYSTAL_PLUS = 9
     VER_CHUNITHM_PARADISE = 10
+
     VER_CHUNITHM_NEW = 11
     VER_CHUNITHM_NEW_PLUS = 12
     VER_CHUNITHM_SUN = 13
     VER_CHUNITHM_SUN_PLUS = 14
     VER_CHUNITHM_LUMINOUS = 15
+
     VERSION_NAMES = [
         "CHUNITHM",
         "CHUNITHM PLUS",
@@ -43,6 +45,37 @@ class ChuniConstants:
         "CHUNITHM LUMINOUS",
     ]
 
+    SCORE_RANK_INTERVALS_OLD = [
+        (1007500, "SSS"),
+        (1000000, "SS"),
+        ( 975000, "S"),
+        ( 950000, "AAA"),
+        ( 925000, "AA"),
+        ( 900000, "A"),
+        ( 800000, "BBB"),
+        ( 700000, "BB"),
+        ( 600000, "B"),
+        ( 500000, "C"),
+        (      0, "D"),
+    ]
+
+    SCORE_RANK_INTERVALS_NEW = [
+        (1009000, "SSS+"),  # New only
+        (1007500, "SSS"),
+        (1005000, "SS+"),  # New only
+        (1000000, "SS"),
+        ( 990000, "S+"),  # New only
+        ( 975000, "S"),
+        ( 950000, "AAA"),
+        ( 925000, "AA"),
+        ( 900000, "A"),
+        ( 800000, "BBB"),
+        ( 700000, "BB"),
+        ( 600000, "B"),
+        ( 500000, "C"),
+        (      0, "D"),
+    ]
+
     @classmethod
     def game_ver_to_string(cls, ver: int):
         return cls.VERSION_NAMES[ver]
diff --git a/titles/chuni/frontend.py b/titles/chuni/frontend.py
index 510ae08..74f7794 100644
--- a/titles/chuni/frontend.py
+++ b/titles/chuni/frontend.py
@@ -13,6 +13,69 @@ from .config import ChuniConfig
 from .const import ChuniConstants
 
 
+def pairwise(iterable):
+    # https://docs.python.org/3/library/itertools.html#itertools.pairwise
+    # but for Python < 3.10. pairwise('ABCDEFG') → AB BC CD DE EF FG
+    iterator = iter(iterable)
+    a = next(iterator, None)
+    for b in iterator:
+        yield a, b
+        a = b
+
+
+def calculate_song_rank(score: int, game_version: int) -> str:
+    if game_version >= ChuniConstants.VER_CHUNITHM_NEW:
+        intervals = ChuniConstants.SCORE_RANK_INTERVALS_NEW
+    else:
+        intervals = ChuniConstants.SCORE_RANK_INTERVALS_OLD
+
+    for (min_score, rank) in intervals:
+        if score >= min_score:
+            return rank
+
+    return "D"
+
+
+def calculate_song_rating(score: int, chart_constant: float, game_version: int) -> float:
+    is_new = game_version >= ChuniConstants.VER_CHUNITHM_NEW
+
+    if is_new:  # New and later
+        max_score = 1009000
+        max_rating_modifier = 2.15
+    else:  # Up to Paradise Lost
+        max_score = 1007500
+        max_rating_modifier = 2.0
+
+    if (score < 500000):
+        return 0.0  # D
+    elif (score >= max_score):
+        return chart_constant + max_rating_modifier  # SSS/SSS+
+
+    # Okay, we're doing this the hard way.
+    # Rating goes up linearly between breakpoints listed below.
+    # Pick the score interval in which we are in, then calculate
+    # the position between possible ratings.
+    score_intervals = [
+        ( 500000, 0.0),  # C
+        ( 800000, max(0.0, (chart_constant - 5.0) / 2)),  # BBB
+        ( 900000, max(0.0, (chart_constant - 5.0))),  # A
+        ( 925000, max(0.0, (chart_constant - 3.0))),  # AA
+        ( 975000, chart_constant),  # S
+        (1000000, chart_constant + 1.0),  # SS
+        (1005000, chart_constant + 1.5),  # SS+
+        (1007500, chart_constant + 2.0),  # SSS
+        (1009000, chart_constant + max_rating_modifier),  # SSS+!
+    ]
+
+    for ((lo_score, lo_rating), (hi_score, hi_rating)) in pairwise(score_intervals):
+        if not (lo_score <= score < hi_score):
+            continue
+
+        interval_pos = (score - lo_score) / (hi_score - lo_score)
+        return lo_rating + ((hi_rating - lo_rating) * interval_pos)
+
+
+
 class ChuniFrontend(FE_Base):
     def __init__(
         self, cfg: CoreConfig, environment: jinja2.Environment, cfg_dir: str
@@ -91,37 +154,27 @@ class ChuniFrontend(FE_Base):
             base_list=[]
             if profile and rating:
                 song_records = []
+
                 for song in rating:
                     music_chart = await self.data.static.get_music_chart(usr_sesh.chunithm_version, song.musicId, song.difficultId)
-                    if music_chart:
-                        if (song.score < 800000):
-                            song_rating = 0
-                        elif (song.score >= 800000 and song.score < 900000):
-                            song_rating = music_chart.level / 2 - 5
-                        elif (song.score >= 900000 and song.score < 925000):
-                            song_rating = music_chart.level - 5
-                        elif (song.score >= 925000 and song.score < 975000):
-                            song_rating = music_chart.level - 3
-                        elif (song.score >= 975000 and song.score < 1000000):
-                            song_rating = (song.score - 975000) / 2500 * 0.1 + music_chart.level
-                        elif (song.score >= 1000000 and song.score < 1005000):
-                            song_rating = (song.score - 1000000) / 1000 * 0.1 + 1 + music_chart.level
-                        elif (song.score >= 1005000 and song.score < 1007500):
-                            song_rating = (song.score - 1005000) / 500 * 0.1 + 1.5 + music_chart.level
-                        elif (song.score >= 1007500 and song.score < 1009000):
-                            song_rating = (song.score - 1007500) / 100 * 0.01 + 2 + music_chart.level
-                        elif (song.score >= 1009000):
-                            song_rating = 2.15 + music_chart.level
-                        song_rating = int(song_rating * 10 ** 2) / 10 ** 2
-                        song_records.append({
-                            "difficultId": song.difficultId,
-                            "musicId": song.musicId,
-                            "title": music_chart.title,
-                            "level": music_chart.level,
-                            "score": song.score,
-                            "type": song.type,
-                            "song_rating": song_rating,
-                        })
+                    if not music_chart:
+                        continue
+
+                    rank = calculate_song_rank(song.score, profile.version)
+                    rating = calculate_song_rating(song.score, music_chart.level, profile.version)
+
+                    song_rating = int(rating * 10 ** 2) / 10 ** 2
+                    song_records.append({
+                        "difficultId": song.difficultId,
+                        "musicId": song.musicId,
+                        "title": music_chart.title,
+                        "level": music_chart.level,
+                        "score": song.score,
+                        "type": song.type,
+                        "rank": rank,
+                        "song_rating": song_rating,
+                    })
+
                 hot_list = [obj for obj in song_records if obj["type"] == "userRatingBaseHotList"]
                 base_list = [obj for obj in song_records if obj["type"] == "userRatingBaseList"]
             return Response(template.render(
@@ -243,4 +296,4 @@ class ChuniFrontend(FE_Base):
                 resp.set_cookie("ARTEMIS_SESH", encoded_sesh)
             return resp
         else:
-            return RedirectResponse("/gate/", 303)
\ No newline at end of file
+            return RedirectResponse("/gate/", 303)
diff --git a/titles/chuni/index.py b/titles/chuni/index.py
index dd49cc6..144f770 100644
--- a/titles/chuni/index.py
+++ b/titles/chuni/index.py
@@ -94,14 +94,19 @@ class ChuniServlet(BaseServlet):
 
         known_iter_counts = {
             ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS: 67,
+            f"{ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS}_int": 25, # SUPERSTAR
             ChuniConstants.VER_CHUNITHM_PARADISE: 44,
-            f"{ChuniConstants.VER_CHUNITHM_PARADISE}_int": 25,
+            f"{ChuniConstants.VER_CHUNITHM_PARADISE}_int": 51, # SUPERSTAR PLUS
             ChuniConstants.VER_CHUNITHM_NEW: 54,
             f"{ChuniConstants.VER_CHUNITHM_NEW}_int": 49,
             ChuniConstants.VER_CHUNITHM_NEW_PLUS: 25,
+            f"{ChuniConstants.VER_CHUNITHM_NEW_PLUS}_int": 31,
             ChuniConstants.VER_CHUNITHM_SUN: 70,
+            f"{ChuniConstants.VER_CHUNITHM_SUN}_int": 35,
             ChuniConstants.VER_CHUNITHM_SUN_PLUS: 36,
+            f"{ChuniConstants.VER_CHUNITHM_SUN_PLUS}_int": 36,
             ChuniConstants.VER_CHUNITHM_LUMINOUS: 8,
+            f"{ChuniConstants.VER_CHUNITHM_LUMINOUS}_int": 8,
         }
 
         for version, keys in self.game_cfg.crypto.keys.items():
@@ -233,8 +238,10 @@ class ChuniServlet(BaseServlet):
           elif version >= 220:  # LUMINOUS
               internal_ver = ChuniConstants.VER_CHUNITHM_LUMINOUS
         elif game_code == "SDGS": # Int
-          if version < 110: # SUPERSTAR / SUPERSTAR PLUS
-              internal_ver = ChuniConstants.VER_CHUNITHM_PARADISE # SUPERSTAR / SUPERSTAR PLUS worked fine with it
+          if version < 105: # SUPERSTAR
+              internal_ver = ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS
+          elif version >= 105 and version < 110: # SUPERSTAR PLUS *Cursed but needed due to different encryption key
+              internal_ver = ChuniConstants.VER_CHUNITHM_PARADISE
           elif version >= 110 and version < 115: # NEW
               internal_ver = ChuniConstants.VER_CHUNITHM_NEW
           elif version >= 115 and version < 120: # NEW PLUS!!
@@ -353,9 +360,9 @@ class ChuniServlet(BaseServlet):
         padded = pad(zipped, 16)
 
         crypt = AES.new(
-            bytes.fromhex(self.game_cfg.crypto.keys[internal_ver][0]),
+            bytes.fromhex(self.game_cfg.crypto.keys[crypto_cfg_key][0]),
             AES.MODE_CBC,
-            bytes.fromhex(self.game_cfg.crypto.keys[internal_ver][1]),
+            bytes.fromhex(self.game_cfg.crypto.keys[crypto_cfg_key][1]),
         )
 
         return Response(crypt.encrypt(padded))
diff --git a/titles/chuni/sun.py b/titles/chuni/sun.py
index 94dc1eb..4957c4b 100644
--- a/titles/chuni/sun.py
+++ b/titles/chuni/sun.py
@@ -16,4 +16,14 @@ class ChuniSun(ChuniNewPlus):
 
         # hardcode lastDataVersion for CardMaker 1.35 A032
         user_data["lastDataVersion"] = "2.10.00"
-        return user_data
\ No newline at end of file
+        return user_data
+
+    #SDGS Exclusive
+    async def handle_get_user_cto_c_play_api_request(self, data: Dict) -> Dict:
+        return {
+            "userId": data["userId"],
+            "orderBy": "0",
+            "count": "0",
+            #game request c2c play history while login but seem unused(?)
+            "userCtoCPlayList": [],
+        }
\ No newline at end of file
diff --git a/titles/chuni/templates/chuni_rating.jinja b/titles/chuni/templates/chuni_rating.jinja
index c094e6f..37ed6d0 100644
--- a/titles/chuni/templates/chuni_rating.jinja
+++ b/titles/chuni/templates/chuni_rating.jinja
@@ -18,6 +18,7 @@
             <th>Music</th>
             <th>Difficulty</th>
             <th>Score</th>
+            <th>Rank</th>
             <th>Rating</th>
           </tr>
           {% for row in hot_list %}
@@ -28,6 +29,7 @@
               {{ row.level }}
             </td>
             <td>{{ row.score }}</td>
+            <td>{{ row.rank }}</td>
             <td class="{% if row.song_rating >= 16 %}rainbow{% endif %}">
               {{ row.song_rating }}
             </td>
@@ -48,6 +50,7 @@
             <th>Music</th>
             <th>Difficulty</th>
             <th>Score</th>
+            <th>Rank</th>
             <th>Rating</th>
           </tr>
           {% for row in base_list %}
@@ -58,6 +61,7 @@
               {{ row.level }}
             </td>
             <td>{{ row.score }}</td>
+            <td>{{ row.rank }}</td>
             <td class="{% if row.song_rating >= 16 %}rainbow{% endif %}">
               {{ row.song_rating }}
             </td>
@@ -76,4 +80,4 @@
   Login to view profile information.
   {% endif %}
 </div>
-{% endblock content %}
\ No newline at end of file
+{% endblock content %}