diff --git a/PKHeX.Core/Editing/PKM/QR/QRMessageUtil.cs b/PKHeX.Core/Editing/PKM/QR/QRMessageUtil.cs
index 0e50efe8f..2c166fb78 100644
--- a/PKHeX.Core/Editing/PKM/QR/QRMessageUtil.cs
+++ b/PKHeX.Core/Editing/PKM/QR/QRMessageUtil.cs
@@ -38,7 +38,8 @@ public static class QRMessageUtil
     {
         if (pk is PK7 pk7)
         {
-            byte[] payload = QR7.GenerateQRData(pk7);
+            Span<byte> payload = stackalloc byte[QR7.SIZE];
+            QR7.SetQRData(pk7, payload);
             return GetMessage(payload);
         }
 
diff --git a/PKHeX.Core/Legality/Encounters/Templates/Gen8/EncounterStatic8U.cs b/PKHeX.Core/Legality/Encounters/Templates/Gen8/EncounterStatic8U.cs
index b52b264b0..c3dc1fff4 100644
--- a/PKHeX.Core/Legality/Encounters/Templates/Gen8/EncounterStatic8U.cs
+++ b/PKHeX.Core/Legality/Encounters/Templates/Gen8/EncounterStatic8U.cs
@@ -75,7 +75,7 @@ public sealed record EncounterStatic8U : EncounterStatic8Nest<EncounterStatic8U>
         return StringConverter8.GetTrashState(pk.OriginalTrainerTrash, name);
     }
 
-    private static ReadOnlySpan<char> GetScientistName(int language) => language switch
+    public static ReadOnlySpan<char> GetScientistName(int language) => language switch
     {
         (int)LanguageID.Japanese => "けんきゅういん",
         (int)LanguageID.English => "Scientist",
diff --git a/PKHeX.Core/Legality/RNG/Algorithms/XorShift128.cs b/PKHeX.Core/Legality/RNG/Algorithms/XorShift128.cs
index 341a4843f..0f1d1b128 100644
--- a/PKHeX.Core/Legality/RNG/Algorithms/XorShift128.cs
+++ b/PKHeX.Core/Legality/RNG/Algorithms/XorShift128.cs
@@ -53,7 +53,8 @@ public ref struct XorShift128
 
     public readonly (uint x, uint y, uint z, uint w) GetState32() => (x, y, z, w);
     public readonly (ulong s0, ulong s1) GetState64() => (s0, s1);
-    public readonly string FullState => $"{State:X32}";
+    public readonly UInt128 FullState() => State;
+    public readonly bool Equals(ulong state0, ulong state1) => s0 == state0 && s1 == state1;
 
     /// <summary>
     /// Gets the next random <see cref="ulong"/>.
diff --git a/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus.cs b/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus.cs
index 63b9873ae..f66757484 100644
--- a/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus.cs
+++ b/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Numerics;
 using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
 
 namespace PKHeX.Core;
 
@@ -8,17 +9,21 @@ namespace PKHeX.Core;
 /// Self-modifying RNG structure that implements xoroshiro128+
 /// </summary>
 /// <remarks>https://en.wikipedia.org/wiki/Xoroshiro128%2B</remarks>
+[StructLayout(LayoutKind.Explicit)]
 public ref struct Xoroshiro128Plus
 {
     public const ulong XOROSHIRO_CONST0= 0x0F4B17A579F18960;
     public const ulong XOROSHIRO_CONST = 0x82A2B175229D6A5B;
 
-    private ulong s0;
-    private ulong s1;
+    [FieldOffset(0x0)] private ulong s0;
+    [FieldOffset(0x8)] private ulong s1;
+    [FieldOffset(0x0)] public readonly UInt128 State;
 
     public Xoroshiro128Plus(ulong s0 = XOROSHIRO_CONST0, ulong s1 = XOROSHIRO_CONST) => (this.s0, this.s1) = (s0, s1);
+    public Xoroshiro128Plus(UInt128 state) => State = state;
     public readonly (ulong s0, ulong s1) GetState() => (s0, s1);
     public readonly UInt128 FullState() => new(s1, s0);
+    public readonly bool Equals(ulong state0, ulong state1) => s0 == state0 && s1 == state1;
 
     /// <summary>
     /// Gets the next random <see cref="ulong"/>.
diff --git a/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus8b.cs b/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus8b.cs
index a0159c252..27c103314 100644
--- a/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus8b.cs
+++ b/PKHeX.Core/Legality/RNG/Algorithms/Xoroshiro128Plus8b.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Numerics;
 using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
 
 namespace PKHeX.Core;
 
@@ -10,14 +11,17 @@ namespace PKHeX.Core;
 /// <remarks>https://en.wikipedia.org/wiki/Xoroshiro128%2B</remarks>
 /// <seealso cref="Xoroshiro128Plus"/>
 /// <remarks>Used by the Brilliant Diamond &amp; Shining Pearl games; differs in how values are yielded by Next calls.</remarks>
+[StructLayout(LayoutKind.Explicit)]
 public ref struct Xoroshiro128Plus8b
 {
-    private ulong s0;
-    private ulong s1;
+    [FieldOffset(0x0)] private ulong s0;
+    [FieldOffset(0x8)] private ulong s1;
+    [FieldOffset(0x0)] public readonly UInt128 State;
 
     public Xoroshiro128Plus8b(ulong s0, ulong s1) => (this.s0, this.s1) = (s0, s1);
+    public Xoroshiro128Plus8b(UInt128 state) => State = state;
     public readonly (ulong s0, ulong s1) GetState() => (s0, s1);
-    public readonly UInt128 FullState() => new(s1, s0);
+    public readonly bool Equals(ulong state0, ulong state1) => s0 == state0 && s1 == state1;
 
     public Xoroshiro128Plus8b(ulong seed)
     {
diff --git a/PKHeX.Core/Legality/Structures/CheckIdentifier.cs b/PKHeX.Core/Legality/Structures/CheckIdentifier.cs
index ee9945a5e..bdca02bbe 100644
--- a/PKHeX.Core/Legality/Structures/CheckIdentifier.cs
+++ b/PKHeX.Core/Legality/Structures/CheckIdentifier.cs
@@ -158,4 +158,9 @@ public enum CheckIdentifier : byte
     /// The <see cref="CheckResult"/> pertains to the <see cref="PKM"/> <see cref="IAwakened"/> values.
     /// </summary>
     AVs,
+
+    /// <summary>
+    /// The <see cref="CheckResult"/> pertains to string <see cref="TrashBytes"/>.
+    /// </summary>
+    TrashBytes,
 }
diff --git a/PKHeX.Core/Saves/SAV3E.cs b/PKHeX.Core/Saves/SAV3E.cs
index 0a7f5cbfa..feff41d84 100644
--- a/PKHeX.Core/Saves/SAV3E.cs
+++ b/PKHeX.Core/Saves/SAV3E.cs
@@ -140,10 +140,12 @@ public sealed class SAV3E : SAV3, IGen3Hoenn, IGen3Joyful, IGen3Wonder, IDaycare
         ];
     }
 
+    private Span<byte> PokeBlockData => Large.AsSpan(0x848, PokeBlock3Case.SIZE);
+
     public PokeBlock3Case PokeBlocks
     {
-        get => new(Large, 0x848);
-        set => SetData(Large.AsSpan(0x848), value.Write());
+        get => new(PokeBlockData);
+        set => value.Write(PokeBlockData);
     }
 
     protected override int SeenOffset2 => 0x988;
diff --git a/PKHeX.Core/Saves/SAV3RS.cs b/PKHeX.Core/Saves/SAV3RS.cs
index 67ca7c73a..0e3d19d68 100644
--- a/PKHeX.Core/Saves/SAV3RS.cs
+++ b/PKHeX.Core/Saves/SAV3RS.cs
@@ -99,10 +99,12 @@ public sealed class SAV3RS : SAV3, IGen3Hoenn, IDaycareRandomState<ushort>
         ];
     }
 
+    private Span<byte> PokeBlockData => Large.AsSpan(0x7F8, PokeBlock3Case.SIZE);
+
     public PokeBlock3Case PokeBlocks
     {
-        get => new(Large, 0x7F8);
-        set => SetData(Large.AsSpan(0x7F8), value.Write());
+        get => new(PokeBlockData);
+        set => value.Write(PokeBlockData);
     }
 
     protected override int SeenOffset2 => 0x938;
diff --git a/PKHeX.Core/Saves/Substructures/Gen3/DecorationInventory3.cs b/PKHeX.Core/Saves/Substructures/Gen3/DecorationInventory3.cs
index 2290b7b56..fa245b911 100644
--- a/PKHeX.Core/Saves/Substructures/Gen3/DecorationInventory3.cs
+++ b/PKHeX.Core/Saves/Substructures/Gen3/DecorationInventory3.cs
@@ -3,7 +3,6 @@ using System.Runtime.InteropServices;
 
 namespace PKHeX.Core;
 
-[StructLayout(LayoutKind.Sequential)]
 public readonly ref struct DecorationInventory3
 {
     public const int SIZE = 150;
diff --git a/PKHeX.Core/Saves/Substructures/Gen3/PokeBlock3Case.cs b/PKHeX.Core/Saves/Substructures/Gen3/PokeBlock3Case.cs
index f4569001f..6127c0db1 100644
--- a/PKHeX.Core/Saves/Substructures/Gen3/PokeBlock3Case.cs
+++ b/PKHeX.Core/Saves/Substructures/Gen3/PokeBlock3Case.cs
@@ -5,18 +5,19 @@ namespace PKHeX.Core;
 public sealed class PokeBlock3Case
 {
     private const int Count = 40;
+    public const int SIZE = Count * PokeBlock3.SIZE;
     public readonly PokeBlock3[] Blocks;
 
-    public PokeBlock3Case(ReadOnlySpan<byte> data, int offset)
+    public PokeBlock3Case(ReadOnlySpan<byte> data)
     {
         Blocks = new PokeBlock3[Count];
         for (int i = 0; i < Blocks.Length; i++)
-            Blocks[i] = PokeBlock3.GetBlock(data, offset + (i * PokeBlock3.SIZE));
+            Blocks[i] = PokeBlock3.GetBlock(data, (i * PokeBlock3.SIZE));
     }
 
     public byte[] Write()
     {
-        byte[] result = new byte[Count*PokeBlock3.SIZE];
+        byte[] result = new byte[SIZE];
         Write(result);
         return result;
     }
diff --git a/PKHeX.Core/Saves/Substructures/Gen3/Swarm3.cs b/PKHeX.Core/Saves/Substructures/Gen3/Swarm3.cs
index 628743e00..c0d710acd 100644
--- a/PKHeX.Core/Saves/Substructures/Gen3/Swarm3.cs
+++ b/PKHeX.Core/Saves/Substructures/Gen3/Swarm3.cs
@@ -1,12 +1,10 @@
 using System;
-using System.Runtime.InteropServices;
 using static PKHeX.Core.Move;
 using static PKHeX.Core.Species;
 using static System.Buffers.Binary.BinaryPrimitives;
 
 namespace PKHeX.Core;
 
-[StructLayout(LayoutKind.Sequential, Pack = 4, Size = SIZE)]
 public sealed class Swarm3(byte[] Data)
 {
     public const int SIZE = 0x14;
diff --git a/Tests/PKHeX.Core.Tests/General/Xoroshiro128Tests.cs b/Tests/PKHeX.Core.Tests/General/Xoroshiro128Tests.cs
index 36350168c..576dd1ee3 100644
--- a/Tests/PKHeX.Core.Tests/General/Xoroshiro128Tests.cs
+++ b/Tests/PKHeX.Core.Tests/General/Xoroshiro128Tests.cs
@@ -28,7 +28,7 @@ public static class Xoroshiro128Tests
         for (int i = 0; i < loop; i++)
         {
             _ = rand.Prev();
-            if (rand.GetState() == (s0, s1))
+            if (rand.Equals(s0, s1))
                 return i;
         }
         return -1;
diff --git a/Tests/PKHeX.Core.Tests/General/Xoroshiro128bTests.cs b/Tests/PKHeX.Core.Tests/General/Xoroshiro128bTests.cs
index b3dd5cd79..b3c694a9c 100644
--- a/Tests/PKHeX.Core.Tests/General/Xoroshiro128bTests.cs
+++ b/Tests/PKHeX.Core.Tests/General/Xoroshiro128bTests.cs
@@ -27,7 +27,7 @@ public static class Xoroshiro128bTests
         for (int i = 0; i < loop; i++)
         {
             _ = rand.Prev();
-            if (rand.GetState() == (s0, s1))
+            if (rand.Equals(s0, s1))
                 return i;
         }
         return -1;
@@ -39,7 +39,7 @@ public static class Xoroshiro128bTests
         for (int i = 0; i < loop; i++)
         {
             _ = rand.Next();
-            if (rand.GetState() == (n0, n1))
+            if (rand.Equals(n0, n1))
                 return i;
         }
         return -1;