diff --git a/src/game/engine/fast_critical_section.cpp b/src/game/engine/fast_critical_section.cpp
new file mode 100644
index 0000000..dea09d6
--- /dev/null
+++ b/src/game/engine/fast_critical_section.cpp
@@ -0,0 +1,41 @@
+#include <std_include.hpp>
+#include "game/game.hpp"
+
+#include "fast_critical_section.hpp"
+
+namespace game::engine
+{
+	FastCriticalSectionScopeRead::FastCriticalSectionScopeRead(native::FastCriticalSection* cs)
+	{
+		this->cs_ = cs;
+		if (this->cs_)
+		{
+			native::Sys_LockRead(this->cs_);
+		}
+	}
+
+	FastCriticalSectionScopeRead::~FastCriticalSectionScopeRead()
+	{
+		if (this->cs_)
+		{
+			native::Sys_UnlockRead(this->cs_);
+		}
+	}
+
+	FastCriticalSectionScopeWrite::FastCriticalSectionScopeWrite(native::FastCriticalSection* cs)
+	{
+		this->cs_ = cs;
+		if (this->cs_)
+		{
+			native::Sys_LockWrite(this->cs_);
+		}
+	}
+
+	FastCriticalSectionScopeWrite::~FastCriticalSectionScopeWrite()
+	{
+		if (this->cs_)
+		{
+			native::Sys_UnlockWrite(this->cs_);
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/game/engine/fast_critical_section.hpp b/src/game/engine/fast_critical_section.hpp
new file mode 100644
index 0000000..378b1f5
--- /dev/null
+++ b/src/game/engine/fast_critical_section.hpp
@@ -0,0 +1,24 @@
+#pragma once
+
+namespace game::engine
+{
+	class FastCriticalSectionScopeRead
+	{
+	public:
+		FastCriticalSectionScopeRead(native::FastCriticalSection* cs);
+		~FastCriticalSectionScopeRead();
+
+	private:
+		native::FastCriticalSection* cs_;
+	};
+
+	class FastCriticalSectionScopeWrite
+	{
+	public:
+		FastCriticalSectionScopeWrite(native::FastCriticalSection* cs);
+		~FastCriticalSectionScopeWrite();
+
+	private:
+		native::FastCriticalSection* cs_;
+	};
+}
diff --git a/src/game/game.cpp b/src/game/game.cpp
index ab02c1a..865a04f 100644
--- a/src/game/game.cpp
+++ b/src/game/game.cpp
@@ -72,6 +72,8 @@ namespace game
 		Sys_Sleep_t Sys_Sleep;
 		Sys_FreeFileList_t Sys_FreeFileList;
 		Sys_MessageBox_t Sys_MessageBox;
+		Sys_LockWrite_t Sys_LockWrite;
+		Sys_TempPriorityEnd_t Sys_TempPriorityEnd;
 
 		PMem_AllocFromSource_NoDebug_t PMem_AllocFromSource_NoDebug;
 
@@ -569,6 +571,13 @@ namespace game
 			InterlockedDecrement(&critSect->readCount);
 		}
 
+		void Sys_UnlockWrite(FastCriticalSection* critSect)
+		{
+			assert(critSect->writeCount > 0);
+			InterlockedDecrement(&critSect->writeCount);
+			Sys_TempPriorityEnd(&critSect->tempPriority);
+		}
+
 		[[noreturn]] void Sys_OutOfMemErrorInternal(const char* filename, int line)
 		{
 			Sys_EnterCriticalSection(CRITSECT_FATAL_ERROR);
@@ -801,6 +810,8 @@ namespace game
 		native::Sys_Sleep = native::Sys_Sleep_t(SELECT_VALUE(0x438600, 0x55F460));
 		native::Sys_FreeFileList = native::Sys_FreeFileList_t(SELECT_VALUE(0x486380, 0x5C4F90));
 		native::Sys_MessageBox = native::Sys_MessageBox_t(SELECT_VALUE(0x4664D0, 0x5CD180));
+		native::Sys_LockWrite = native::Sys_LockWrite_t(SELECT_VALUE(0x4C9E70, 0x5502D0));
+		native::Sys_TempPriorityEnd = native::Sys_TempPriorityEnd_t(SELECT_VALUE(0x4DCF00, 0x4C8CF0));
 
 		native::PMem_AllocFromSource_NoDebug = native::PMem_AllocFromSource_NoDebug_t(SELECT_VALUE(0x449E50, 0x5C15C0));
 
diff --git a/src/game/game.hpp b/src/game/game.hpp
index 8b272b3..bbef7cf 100644
--- a/src/game/game.hpp
+++ b/src/game/game.hpp
@@ -164,6 +164,12 @@ namespace game
 		typedef int (*Sys_MessageBox_t)(const char* lpText, const char* lpCaption, unsigned int uType, int defaultValue);
 		extern Sys_MessageBox_t Sys_MessageBox;
 
+		typedef void (*Sys_LockWrite_t)(FastCriticalSection* critSect);
+		extern Sys_LockWrite_t Sys_LockWrite;
+
+		typedef void (*Sys_TempPriorityEnd_t)(TempPriority*);
+		extern Sys_TempPriorityEnd_t Sys_TempPriorityEnd;
+
 		typedef void* (*PMem_AllocFromSource_NoDebug_t)(unsigned int size, unsigned int alignment, unsigned int type, int source);
 		extern PMem_AllocFromSource_NoDebug_t PMem_AllocFromSource_NoDebug;
 
@@ -427,6 +433,7 @@ namespace game
 		bool Sys_IsServerThread();
 		void Sys_LockRead(FastCriticalSection* critSect);
 		void Sys_UnlockRead(FastCriticalSection* critSect);
+		void Sys_UnlockWrite(FastCriticalSection* critSect);
 		[[noreturn]] void Sys_OutOfMemErrorInternal(const char* filename, int line);
 
 		bool FS_Initialized();
diff --git a/src/std_include.hpp b/src/std_include.hpp
index e3f2fd5..af48ceb 100644
--- a/src/std_include.hpp
+++ b/src/std_include.hpp
@@ -39,6 +39,7 @@
 #endif
 
 #include <atomic>
+#include <cassert>
 #include <chrono>
 #include <filesystem>
 #include <format>