diff --git a/PKHeX.Core/PKM/BK4.cs b/PKHeX.Core/PKM/BK4.cs
index a87397e46..aca2a8fd5 100644
--- a/PKHeX.Core/PKM/BK4.cs
+++ b/PKHeX.Core/PKM/BK4.cs
@@ -10,7 +10,7 @@ public sealed class BK4 : _K4
         {
             0x42, 0x43, 0x5E, 0x63, 0x64, 0x65, 0x66, 0x67, 0x87
         };
-        public override int SIZE_PARTY => PKX.SIZE_4PARTY;
+        public override int SIZE_PARTY => PKX.SIZE_4STORED;
         public override int SIZE_STORED => PKX.SIZE_4STORED;
         public override int Format => 4;
         public override PersonalInfo PersonalInfo => PersonalTable.HGSS[Species];
@@ -29,13 +29,13 @@ public BK4(byte[] decryptedData = null, string ident = null)
                 RefreshChecksum();
             if (Valid && Sanity == 0)
                 Sanity = 0x4000;
-            if (Data.Length != SIZE_PARTY)
-                Array.Resize(ref Data, SIZE_PARTY);
+            SetStats(GetStats(PersonalInfo));
         }
         public BK4()
         {
             Data = new byte[SIZE_PARTY];
             Sanity = 0x4000;
+            SetStats(GetStats(PersonalInfo));
         }
         public override PKM Clone() => new BK4((byte[])Encrypt().Clone(), Identifier);
 
@@ -322,14 +322,15 @@ public override int Ball
         // Unused 0x87
         #endregion
 
-        public override int Stat_Level { get => Data[0x8C]; set => Data[0x8C] = (byte)value; }
-        public override int Stat_HPCurrent { get => BigEndian.ToUInt16(Data, 0x8E); set => BigEndian.GetBytes((ushort)value).CopyTo(Data, 0x8E); }
-        public override int Stat_HPMax { get => BigEndian.ToUInt16(Data, 0x90); set => BigEndian.GetBytes((ushort)value).CopyTo(Data, 0x90); }
-        public override int Stat_ATK { get => BigEndian.ToUInt16(Data, 0x92); set => BigEndian.GetBytes((ushort)value).CopyTo(Data, 0x92); }
-        public override int Stat_DEF { get => BigEndian.ToUInt16(Data, 0x94); set => BigEndian.GetBytes((ushort)value).CopyTo(Data, 0x94); }
-        public override int Stat_SPE { get => BigEndian.ToUInt16(Data, 0x96); set => BigEndian.GetBytes((ushort)value).CopyTo(Data, 0x96); }
-        public override int Stat_SPA { get => BigEndian.ToUInt16(Data, 0x98); set => BigEndian.GetBytes((ushort)value).CopyTo(Data, 0x98); }
-        public override int Stat_SPD { get => BigEndian.ToUInt16(Data, 0x9A); set => BigEndian.GetBytes((ushort)value).CopyTo(Data, 0x9A); }
+        // Not stored
+        public override int Stat_Level { get => CurrentLevel; set {} }
+        public override int Stat_HPCurrent { get; set; }
+        public override int Stat_HPMax { get; set; }
+        public override int Stat_ATK { get; set; }
+        public override int Stat_DEF { get; set; }
+        public override int Stat_SPE { get; set; }
+        public override int Stat_SPA { get; set; }
+        public override int Stat_SPD { get; set; }
 
         // Methods
         protected override ushort CalculateChecksum()
diff --git a/PKHeX.Core/Saves/SAV4BR.cs b/PKHeX.Core/Saves/SAV4BR.cs
index 2094b8c8d..4efe462b8 100644
--- a/PKHeX.Core/Saves/SAV4BR.cs
+++ b/PKHeX.Core/Saves/SAV4BR.cs
@@ -75,11 +75,17 @@ public int CurrentSlot
         {
             get => _currentSlot;
             // 4 save slots, data reading depends on current slot
-            set => Box = 0x978 + 0x6FF00 * (_currentSlot = value);
+            set
+            {
+                _currentSlot = value;
+                var ofs = 0x6FF00 * _currentSlot;
+                Box = ofs + 0x978;
+                Party = ofs + 0x65F48; // near the end of the slot chunk
+            }
         }
 
         public override int SIZE_STORED => PKX.SIZE_4STORED;
-        protected override int SIZE_PARTY => PKX.SIZE_4PARTY - 0x10; // PBR has a party
+        protected override int SIZE_PARTY => PKX.SIZE_4STORED + 4;
         public override PKM BlankPKM => new BK4();
         public override Type PKMType => typeof(BK4);
 
@@ -98,7 +104,19 @@ public int CurrentSlot
         public override int MaxMoney => 999999;
 
         public override int BoxCount => 18;
-        public override bool HasParty => false;
+
+        public override int PartyCount
+        {
+            get
+            {
+                int ctr = 0;
+                for (int i = 0; i < 6; i++)
+                    if (Data[GetPartyOffset(i) + 4] != 0) // sanity
+                        ctr += 1;
+                return ctr;
+            }
+            protected set { }
+        }
 
         // Checksums
         protected override void SetChecksums()
@@ -125,7 +143,7 @@ public static bool IsChecksumsValid(byte[] sav)
         // Storage
         public override int GetPartyOffset(int slot) // TODO
         {
-            return -1;
+            return Party + SIZE_PARTY * slot;
         }
         public override int GetBoxOffset(int box)
         {
@@ -157,6 +175,11 @@ protected override void SetPKM(PKM pkm)
                 pkm.RefreshChecksum();
         }
 
+        protected override void SetPartyValues(PKM pkm, bool isParty)
+        {
+            pkm.Sanity = (ushort)(isParty ? 0xC000 : 0x4000);
+        }
+
         public static byte[] DecryptPBRSaveData(byte[] input)
         {
             byte[] output = new byte[input.Length];