diff --git a/r5dev/core/init.cpp b/r5dev/core/init.cpp
index 6415b139..16760c61 100644
--- a/r5dev/core/init.cpp
+++ b/r5dev/core/init.cpp
@@ -6,7 +6,6 @@
 
 #include "core/stdafx.h"
 #include "core/init.h"
-#include "common/opcodes.h"
 #include "tier0/ConCommand.h"
 #include "tier0/completion.h"
 #include "tier0/cvar.h"
@@ -15,11 +14,13 @@
 #include "vpc/keyvalues.h"
 #include "vpc/basefilesystem.h"
 #include "vpc/keyvalues.h"
+#include "common/opcodes.h"
 #include "launcher/IApplication.h"
 #include "ebisusdk/EbisuSDK.h"
 #include "vphysics/QHull.h"
 #include "bsplib/bsplib.h"
 #ifndef DEDICATED
+#include "materialsystem/materialsystem.h"
 #include "vgui/CEngineVGui.h"
 #include "vgui/vgui_fpspanel.h"
 #include "vguimatsurface/MatSystemSurface.h"
@@ -42,6 +43,7 @@
 #include "engine/sys_dll2.h"
 #include "engine/sys_utils.h"
 #ifndef DEDICATED
+#include "engine/debugoverlay.h"
 #include "inputsystem/inputsystem.h"
 #include "windows/id3dx.h"
 #endif // !DEDICATED
diff --git a/r5dev/engine/debugoverlay.h b/r5dev/engine/debugoverlay.h
new file mode 100644
index 00000000..8fdc2cb8
--- /dev/null
+++ b/r5dev/engine/debugoverlay.h
@@ -0,0 +1,147 @@
+#pragma once
+#include "mathlib/vector.h"
+#include "mathlib/color.h"
+
+// Something has to be hardcoded..
+#if defined (GAMEDLL_S0) || defined (GAMEDLL_S1) || defined (GAMEDLL_S2)
+
+constexpr auto MATERIALSYSTEM_VCALL_OFF_0 0x3F8;
+constexpr auto CMATQUEUEDRENDERCONTEXT_VCALL_OFS_0 0x278;
+constexpr auto CMATQUEUEDRENDERCONTEXT_VCALL_OFS_1 0x280;
+
+#elif defined (GAMEDLL_S3)
+
+constexpr auto MATERIALSYSTEM_VCALL_OFF_0 = 0x3F0;
+constexpr auto CMATQUEUEDRENDERCONTEXT_VCALL_OFS_0 = 0x288;
+constexpr auto CMATQUEUEDRENDERCONTEXT_VCALL_OFS_1 = 0x290;
+
+#endif
+constexpr auto CMATQUEUEDRENDERCONTEXT_VCALL_OFS_2 = 0x8;
+constexpr auto NDEBUG_PERSIST_TILL_NEXT_SERVER = (0.01023f);
+
+enum class OverlayType_t
+{
+	OVERLAY_BOX = 0,
+	OVERLAY_SPHERE,
+	OVERLAY_LINE,
+	OVERLAY_TRIANGLE,
+	OVERLAY_SWEPT_BOX,
+	OVERLAY_BOX2,
+	OVERLAY_CAPSULE,
+	OVERLAY_UNK0,
+	OVERLAY_UNK1
+};
+
+struct OverlayBase_t
+{
+	OverlayBase_t()
+	{
+		m_Type          = OverlayType_t::OVERLAY_BOX;
+		m_nServerCount  = -1;
+		m_nCreationTick = -1;
+		m_flEndTime     = 0.0f;
+		m_pNextOverlay  = NULL;
+		unk0            = NULL;
+	}
+	bool IsDead();
+
+	OverlayType_t   m_Type         {}; // What type of overlay is it?
+	int             m_nCreationTick{}; // Duration -1 means go away after this frame #
+	float           m_nServerCount {}; // Latch server count, too
+	float           m_flEndTime    {}; // When does this box go away
+	OverlayBase_t*  m_pNextOverlay {}; // 16
+	int64_t         unk0           {}; // 24
+};
+
+struct OverlayLine_t : public OverlayBase_t
+{
+	OverlayLine_t() { m_Type = OverlayType_t::OVERLAY_LINE; }
+
+	Vector3         origin{};
+	Vector3         dest{};
+	int             r{};
+	int             g{};
+	int             b{};
+	int             a{};
+	bool            noDepthTest{};
+};
+
+struct OverlayBox_t : public OverlayBase_t
+{
+	OverlayBox_t() { m_Type = OverlayType_t::OVERLAY_BOX; }
+
+	Vector3         origin{};
+	Vector3         mins{};
+	Vector3         maxs{};
+	QAngle          angles{};
+	int             r{};
+	int             g{};
+	int             b{};
+	int             a{};
+};
+
+void HDestroyOverlay(OverlayBase_t* pOverlay);
+void DrawOverlay(OverlayBase_t* pOverlay);
+void DebugOverlays_Attach();
+void DebugOverlays_Detach();
+
+namespace
+{
+#if defined (GAMEDLL_S0) || defined (GAMEDLL_S1)
+	ADDRESS p_DrawAllOverlays = g_mGameDll.FindPatternSIMD((std::uint8_t*)"\x40\x55\x48\x83\xEC\x50\x48\x8B\x05\x00\x00\x00\x00", "xxxxxxxxx????");
+	void (*DrawAllOverlays)(char a1) = (void (*)(char))p_DrawAllOverlays.GetPtr(); /*40 55 48 83 EC 50 48 8B 05 ? ? ? ?*/
+
+	ADDRESS p_RenderBox = g_mGameDll.FindPatternSIMD((std::uint8_t*)"\x48\x89\x5C\x24\x00\x48\x89\x6C\x24\x00\x44\x89\x4C\x24\x00", "xxxx?xxxx?xxxx?"); /*48 89 5C 24 ? 48 89 6C 24 ? 44 89 4C 24 ?*/
+	void* (*RenderBox)(Vector3 origin, QAngle angles, Vector3 vMins, Vector3 vMaxs, Color color, bool bZBuffer) = (void* (*)(Vector3, QAngle, Vector3, Vector3, Color, bool))p_RenderBox.GetPtr();
+#elif defined (GAMEDLL_S2) || defined (GAMEDLL_S3)
+	ADDRESS p_DrawAllOverlays = g_mGameDll.FindPatternSIMD((std::uint8_t*)"\x40\x55\x48\x83\xEC\x30\x48\x8B\x05\x00\x00\x00\x00\x0F\xB6\xE9", "xxxxxxxxx????xxx");
+	void (*DrawAllOverlays)(char a1) = (void (*)(char))p_DrawAllOverlays.GetPtr(); /*40 55 48 83 EC 30 48 8B 05 ? ? ? ? 0F B6 E9*/
+
+	ADDRESS p_RenderBox = g_mGameDll.FindPatternSIMD((std::uint8_t*)"\x48\x89\x5C\x24\x00\x48\x89\x6C\x24\x00\x44\x89\x4C\x24\x00", "xxxx?xxxx?xxxx?"); /*48 89 5C 24 ? 48 89 6C 24 ? 44 89 4C 24 ?*/
+	void* (*RenderBox)(Vector3 origin, QAngle angles, Vector3 vMins, Vector3 vMaxs, Color color, bool bZBuffer) = (void* (*)(Vector3, QAngle, Vector3, Vector3, Color, bool))p_RenderBox.GetPtr();
+#endif
+	ADDRESS p_RenderLine = g_mGameDll.FindPatternSIMD((std::uint8_t*)"\x48\x89\x74\x24\x00\x44\x89\x44\x24\x00\x57\x41\x56", "xxxx?xxxx?xxx"); /*48 89 74 24 ? 44 89 44 24 ? 57 41 56*/
+	void* (*RenderLine)(Vector3 origin, Vector3 dest, Color color, bool bZBuffer) = (void* (*)(Vector3, Vector3, Color, bool))p_RenderLine.GetPtr();
+
+	ADDRESS p_DestroyOverlay = g_mGameDll.FindPatternSIMD((std::uint8_t*)"\x40\x53\x48\x83\xEC\x20\x48\x8B\xD9\x48\x8D\x0D\x00\x00\x00\x00\xFF\x15\x00\x00\x00\x00\x48\x63\x03", "xxxxxxxxxxxx????xx????xxx");
+	void (*DestroyOverlay)(void* pOverlay) = (void (*)(void*))p_DestroyOverlay.GetPtr(); /*40 53 48 83 EC 20 48 8B D9 48 8D 0D ? ? ? ? FF 15 ? ? ? ? 48 63 03 */
+
+	int* client_debugdraw_int_unk = p_DrawAllOverlays.Offset(0xC0).FindPatternSelf("F3 0F 59", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x4, 0x8).RCast<int*>();
+	float* client_debugdraw_float_unk = p_DrawAllOverlays.Offset(0xD0).FindPatternSelf("F3 0F 10", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x4, 0x8).RCast<float*>();
+
+	OverlayBase_t** s_pOverlays = p_DrawAllOverlays.Offset(0x10).FindPatternSelf("48 8B 3D", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x3, 0x7).RCast<OverlayBase_t**>();
+	LPCRITICAL_SECTION s_OverlayMutex = p_DrawAllOverlays.Offset(0x10).FindPatternSelf("48 8D 0D", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x3, 0x7).RCast<LPCRITICAL_SECTION>();
+
+#if defined (GAMEDLL_S0) || defined (GAMEDLL_S1)
+	int* render_tickcount = p_DrawAllOverlays.Offset(0x80).FindPatternSelf("3B 0D 17", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x2, 0x6).RCast<int*>();
+	int* overlay_tickcount = p_DrawAllOverlays.Offset(0x70).FindPatternSelf("3B 0D", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x2, 0x6).RCast<int*>();
+#elif defined (GAMEDLL_S2)
+	int* render_tickcount = p_DrawAllOverlays.Offset(0x50).FindPatternSelf("3B 05 79", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x2, 0x6).RCast<int*>();
+	int* overlay_tickcount = p_DrawAllOverlays.Offset(0x70).FindPatternSelf("3B 05", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x2, 0x6).RCast<int*>();
+#elif defined (GAMEDLL_S3)
+	int* render_tickcount = p_DrawAllOverlays.Offset(0x50).FindPatternSelf("3B 05 B1", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x2, 0x6).RCast<int*>();
+	int* overlay_tickcount = p_DrawAllOverlays.Offset(0x70).FindPatternSelf("3B 05", ADDRESS::Direction::DOWN, 150).ResolveRelativeAddressSelf(0x2, 0x6).RCast<int*>();
+#endif
+}
+
+///////////////////////////////////////////////////////////////////////////////
+class HDebugOverlay : public IDetour
+{
+	virtual void debugp()
+	{
+		std::cout << "| FUN: DrawAllOverlays                      : 0x" << std::hex << std::uppercase << p_DrawAllOverlays.GetPtr() << std::setw(npad) << " |" << std::endl;
+		std::cout << "| FUN: RenderBox                            : 0x" << std::hex << std::uppercase << p_RenderBox.GetPtr()       << std::setw(npad) << " |" << std::endl;
+		std::cout << "| FUN: RenderLine                           : 0x" << std::hex << std::uppercase << p_RenderLine.GetPtr()      << std::setw(npad) << " |" << std::endl;
+		std::cout << "| FUN: DestroyOverlay                       : 0x" << std::hex << std::uppercase << p_DestroyOverlay.GetPtr()  << std::setw(npad) << " |" << std::endl;
+		std::cout << "| VAR: s_pOverlays                          : 0x" << std::hex << std::uppercase << s_pOverlays                << std::setw(0) << " |" << std::endl;
+		std::cout << "| VAR: s_OverlayMutex                       : 0x" << std::hex << std::uppercase << s_OverlayMutex             << std::setw(0) << " |" << std::endl;
+		std::cout << "| VAR: client_debugdraw_int_unk             : 0x" << std::hex << std::uppercase << client_debugdraw_int_unk   << std::setw(0) << " |" << std::endl;
+		std::cout << "| VAR: client_debugdraw_float_unk           : 0x" << std::hex << std::uppercase << client_debugdraw_float_unk << std::setw(0) << " |" << std::endl;
+		std::cout << "| VAR: overlay_tickcount                    : 0x" << std::hex << std::uppercase << overlay_tickcount          << std::setw(0) << " |" << std::endl;
+		std::cout << "| VAR: render_tickcount                     : 0x" << std::hex << std::uppercase << render_tickcount           << std::setw(0) << " |" << std::endl;
+		std::cout << "+----------------------------------------------------------------+" << std::endl;
+	}
+};
+///////////////////////////////////////////////////////////////////////////////
+
+REGISTER(HDebugOverlay);
diff --git a/r5dev/r5dev.vcxproj b/r5dev/r5dev.vcxproj
index f02675d0..c394b569 100644
--- a/r5dev/r5dev.vcxproj
+++ b/r5dev/r5dev.vcxproj
@@ -126,6 +126,7 @@
     <ClInclude Include="ebisusdk\EbisuSDK.h" />
     <ClInclude Include="engine\baseclient.h" />
     <ClInclude Include="engine\baseclientstate.h" />
+    <ClInclude Include="engine\debugoverlay.h" />
     <ClInclude Include="engine\host_cmd.h" />
     <ClInclude Include="engine\host_state.h" />
     <ClInclude Include="engine\net_chan.h" />
diff --git a/r5dev/r5dev.vcxproj.filters b/r5dev/r5dev.vcxproj.filters
index 921368fd..00585ed7 100644
--- a/r5dev/r5dev.vcxproj.filters
+++ b/r5dev/r5dev.vcxproj.filters
@@ -854,6 +854,9 @@
     <ClInclude Include="materialsystem\materialsystem.h">
       <Filter>sdk\materialsystem</Filter>
     </ClInclude>
+    <ClInclude Include="engine\debugoverlay.h">
+      <Filter>sdk\engine</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <None Include="r5dev.def" />