diff --git a/PKHeX.Core/Saves/SAV8BS.cs b/PKHeX.Core/Saves/SAV8BS.cs
index 2e7871bcf..43e53c96a 100644
--- a/PKHeX.Core/Saves/SAV8BS.cs
+++ b/PKHeX.Core/Saves/SAV8BS.cs
@@ -33,7 +33,7 @@ namespace PKHeX.Core
             Contest = new Contest8b(this, 0x79C08); // size: 0x720
 
             Zukan = new Zukan8b(this, 0x7A328); // size: 0x30B8
-            // 0x7D3E0 - Trainer Battle Data (bool,bool)[707]
+            BattleTrainer = new BattleTrainerStatus8b(this, 0x7D3E0); // size: 0x1618
             // 0x7E9F8 - Menu selections (TopMenuItemTypeInt32, bool IsNew)[8], TopMenuItemTypeInt32 LastSelected
             // 0x7EA3C - _FIELDOBJ_SAVE Objects[1000] (sizeof (0x44, 17 int fields), total size 0x109A0
             Records = new Record8b(this, 0x8F3DC); // size: 0x78
@@ -53,8 +53,8 @@ namespace PKHeX.Core
             // BoukenNote
             // TV_DATA
             // UgSaveData
-            // GMS_DATA
-            // PLAYER_NETWORK_DATA
+            // 0x9D03C - GMS_DATA // size: 0x31304
+            // 0xCE340 - PLAYER_NETWORK_DATA
             // UnionSaveData
             // CON_PHOTO_LANG_DATA -- contest photo language data
             // ZUKAN_PERSONAL_RND_DATA
@@ -188,6 +188,7 @@ namespace PKHeX.Core
         public Contest8b Contest { get; }
         // public Misc8 Misc { get; }
         public Zukan8b Zukan { get; }
+        public BattleTrainerStatus8b BattleTrainer { get; }
         public Record8b Records { get; }
         public BerryTreeGrowSave8b BerryTrees { get; }
         public PoffinSaveData8b Poffins { get; }
diff --git a/PKHeX.Core/Saves/Substructures/Gen8/BS/BattleTrainerStatus8b.cs b/PKHeX.Core/Saves/Substructures/Gen8/BS/BattleTrainerStatus8b.cs
new file mode 100644
index 000000000..59f06d9b7
--- /dev/null
+++ b/PKHeX.Core/Saves/Substructures/Gen8/BS/BattleTrainerStatus8b.cs
@@ -0,0 +1,54 @@
+using System;
+
+namespace PKHeX.Core
+{
+    /// <summary>
+    /// Defeated Status for all trainers (Dpr.Trainer.TrainerID)
+    /// </summary>
+    /// <remarks>size: 0x1618</remarks>
+    public sealed class BattleTrainerStatus8b : SaveBlock
+    {
+        public BattleTrainerStatus8b(SAV8BS sav, int offset) : base(sav) => Offset = offset;
+
+        // Structure:
+        // (bool IsWin, bool IsBattleSearcher)[707];
+        private const int COUNT_TRAINER = 707;
+        private const int SIZE_TRAINER = 8; // bool,bool
+
+        /// <summary>
+        /// Don't use this unless you've finished the post-game.
+        /// </summary>
+        public void DefeatAll()
+        {
+            for (int i = 0; i < COUNT_TRAINER; i++)
+            {
+                SetIsWin(i, true);
+                SetIsBattleSearcher(i, false);
+            }
+        }
+
+        /// <summary>
+        /// Don't use this unless you've finished the post-game.
+        /// </summary>
+        public void RebattleAll()
+        {
+            for (int i = 0; i < COUNT_TRAINER; i++)
+            {
+                SetIsWin(i, true);
+                SetIsBattleSearcher(i, true);
+            }
+        }
+
+        private int GetTrainerOffset(int trainer)
+        {
+            if ((uint)trainer >= COUNT_TRAINER)
+                throw new ArgumentOutOfRangeException(nameof(trainer));
+            return Offset + (trainer * SIZE_TRAINER);
+        }
+
+        public bool GetIsWin(int trainer) => BitConverter.ToUInt32(Data, GetTrainerOffset(trainer)) == 1;
+        public bool GetIsBattleSearcher(int trainer) => BitConverter.ToUInt32(Data, GetTrainerOffset(trainer) + 4) == 1;
+        public void SetIsWin(int trainer, bool value) => BitConverter.GetBytes(value ? 1u : 0u).CopyTo(Data, GetTrainerOffset(trainer));
+        public void SetIsBattleSearcher(int trainer, bool value) => BitConverter.GetBytes(value ? 1u : 0u).CopyTo(Data, GetTrainerOffset(trainer) + 4);
+    }
+}