diff --git a/CREDITS.md b/CREDITS.md
index 44c87160fb..0ecdb72b92 100644
--- a/CREDITS.md
+++ b/CREDITS.md
@@ -290,6 +290,7 @@ This page lists all the individual contributions to the project by their author.
   - Guard range customizations
   - Wall overlay unit sell exploit fix
   - Fix vehicles disguised as trees incorrectly displaying veterancy insignia when they shouldn't
+  - GapGen + SpySat desync fix
 - **Morton (MortonPL)**:
   - `XDrawOffset` for animations
   - Shield passthrough & absorption
diff --git a/docs/Fixed-or-Improved-Logics.md b/docs/Fixed-or-Improved-Logics.md
index 6c2070cb3b..b06faee175 100644
--- a/docs/Fixed-or-Improved-Logics.md
+++ b/docs/Fixed-or-Improved-Logics.md
@@ -315,6 +315,7 @@ This page describes all ingame logics that are fixed or improved in Phobos witho
 - Fixed an issue where a unit might cause the target to fall from above its own head when using a locomotor warhead with `Locomotor=Jumpjet` to pull a target with `BalloonHover=yes`.
 - Fixed the [EIP#007120F7](https://modenc.renegadeprojects.com/Internal_Error#eip_007120F7) that was triggered when repairing because the `Strength` value was lower than `RepairStep`.
 - Fixed the bug where non-Teleporter miners would not return to work after minerals are depleted and then regenerated.
+- Fixed a desync due to an inconsistent shroud state caused by `GapGenerator` and `SpySat` interaction.
 
 ## Fixes / interactions with other extensions
 
diff --git a/docs/Whats-New.md b/docs/Whats-New.md
index 39685cd218..442f44181a 100644
--- a/docs/Whats-New.md
+++ b/docs/Whats-New.md
@@ -692,6 +692,7 @@ Fixes / interactions with other extensions:
 
 Vanilla fixes:
 - Vehicles overlapping `Wall=true` OverlayTypes no longer display sell cursor and cannot be sold (by CnCRAZER & Starkku)
+- Fixed a desync due to an inconsistent shroud state caused by `GapGenerator` and `SpySat` interaction (by Starkku)
 
 Phobos fixes:
 - Fixed vehicles disguised as trees incorrectly displaying veterancy insignia when they shouldn't (by Starkku)
diff --git a/src/Misc/Hooks.BugFixes.cpp b/src/Misc/Hooks.BugFixes.cpp
index 63873b28c9..2cc9a3adb6 100644
--- a/src/Misc/Hooks.BugFixes.cpp
+++ b/src/Misc/Hooks.BugFixes.cpp
@@ -3275,3 +3275,92 @@ DEFINE_HOOK(0x7120DD, TechnoTypeClass_GetRepairStepCost, 0x6)
 
 	return SkipGameCode;
 }
+
+#pragma region ShroudFix
+
+// These map cells are what SpySat skips revealing in MP normally.
+static bool inline ShroudFix_IsCellInvalid(CellStruct* pMapCell)
+{
+	const int x = pMapCell->X;
+	const int y = pMapCell->Y;
+	auto const& rect = MapClass::Instance.MapRect;
+
+	if (x == 7 && y == rect.Width + 5)
+		return true;
+
+	if (x == 13 && y == rect.Width + 11)
+		return true;
+
+	if (x == rect.Height + 13 && y == rect.Width + rect.Height - 15)
+		return true;
+
+	return false;
+}
+
+DEFINE_HOOK(0x6FB5E5, TechnoClass_DeleteGap_CellCheck, 0x5)
+{
+	enum { SkipCell = 0x6FB6F3 };
+
+	GET(CellStruct*, pMapCell, EDX);
+
+	if (ShroudFix_IsCellInvalid(pMapCell))
+		return SkipCell;
+
+	return 0;
+}
+
+DEFINE_HOOK(0x6FB2FB, TechnoClass_CreateGap_CellCheck, 0x5)
+{
+	enum { SkipCell = 0x6FB416 };
+
+	GET(CellStruct*, pMapCell, EDX);
+
+	if (ShroudFix_IsCellInvalid(pMapCell))
+		return SkipCell;
+
+	return 0;
+}
+
+// Replace the entire cell iterator loop for perf reasons.
+DEFINE_HOOK(0x577AFF, MapClass_ResetShroud_CellCheck, 0x6)
+{
+	enum { SkipGameCode = 0x577B75 };
+
+	auto& map = MapClass::Instance;
+	map.CellIteratorReset();
+
+	for (auto pCell = map.CellIteratorNext(); pCell; pCell = map.CellIteratorNext())
+	{
+		if (ShroudFix_IsCellInvalid(&pCell->MapCoords))
+			continue;
+
+		pCell->Flags &= ~(CellFlags::CenterRevealed | CellFlags::EdgeRevealed);
+		pCell->AltFlags &= ~(AltCellFlags::Mapped | AltCellFlags::NoFog);
+		pCell->ShroudCounter = 1;
+		pCell->GapsCoveringThisCell = 0;
+	}
+
+	return SkipGameCode;
+}
+
+// Replace the entire cell iterator loop for perf reasons.
+DEFINE_HOOK(0x577BF1, MapClass_ResetShroudForTMission_CellCheck, 0x6)
+{
+	enum { SkipGameCode = 0x577C57 };
+
+	auto& map = MapClass::Instance;
+	map.CellIteratorReset();
+
+	for (auto pCell = map.CellIteratorNext(); pCell; pCell = map.CellIteratorNext())
+	{
+		if (ShroudFix_IsCellInvalid(&pCell->MapCoords))
+			continue;
+
+		pCell->Flags &= ~(CellFlags::CenterRevealed | CellFlags::EdgeRevealed);
+		pCell->AltFlags &= ~(AltCellFlags::Mapped | AltCellFlags::NoFog);
+	}
+
+	return SkipGameCode;
+}
+
+#pragma endregion
diff --git a/src/Phobos.cpp b/src/Phobos.cpp
index c061b50170..60ce544c2f 100644
--- a/src/Phobos.cpp
+++ b/src/Phobos.cpp
@@ -271,6 +271,18 @@ void Phobos::ApplyOptimizations()
 
 	if (!SessionClass::IsMultiplayer())
 	{
+		// Disable TechnoClass_DeleteGap_CellCheck
+		Patch::Apply_RAW(0x6FB5E5, { 0xB9, 0xE8, 0xF7, 0x87, 0x00 });
+
+		// Disable TechnoClass_CreateGap_CellCheck
+		Patch::Apply_RAW(0x6FB2FB, { 0xB9, 0xE8, 0xF7, 0x87, 0x00 });
+
+		// Disable MapClass_ResetShroud_CellCheck
+		Patch::Apply_RAW(0x577AFF, { 0x8B, 0x86, 0xF4, 0x00, 0x00, 0x00 });
+
+		// Disable MapClass_ResetShroudForTMission_CellCheck
+		Patch::Apply_RAW(0x577BF1, { 0x8B, 0x86, 0xF4, 0x00, 0x00, 0x00 });
+
 		// Disable Random2Class_Random_SyncLog
 		Patch::Apply_RAW(0x65C7D0, { 0xC3, 0x90, 0x90, 0x90, 0x90 });