diff --git a/dlls/COFAllyMonster.h b/dlls/COFAllyMonster.h
index e42c9f3f..95a87d4f 100644
--- a/dlls/COFAllyMonster.h
+++ b/dlls/COFAllyMonster.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef COFALLYMONSTER_H
-#define COFALLYMONSTER_H
+
+#pragma once
 
 /**
 *	@brief Base class for Opposing force allies
@@ -95,5 +95,3 @@ class COFAllyMonster : public CBaseMonster
 	EHANDLE		m_hTalkTarget;	// who to look at while talking
 	CUSTOM_SCHEDULES;
 };
-
-#endif
diff --git a/dlls/ctf/CItemAcceleratorCTF.h b/dlls/ctf/CItemAcceleratorCTF.h
index f0b14e0f..3b62970e 100644
--- a/dlls/ctf/CItemAcceleratorCTF.h
+++ b/dlls/ctf/CItemAcceleratorCTF.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CITEMACCELERATORCTF_H
-#define CITEMACCELERATORCTF_H
+
+#pragma once
 
 #include "CItemCTF.h"
 
@@ -30,5 +30,3 @@ class CItemAcceleratorCTF : public CItemCTF
 
 	bool MyTouch( CBasePlayer* pPlayer ) override;
 };
-
-#endif
diff --git a/dlls/ctf/CItemBackpackCTF.h b/dlls/ctf/CItemBackpackCTF.h
index 19c5e91d..205c206a 100644
--- a/dlls/ctf/CItemBackpackCTF.h
+++ b/dlls/ctf/CItemBackpackCTF.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CITEMBACKPACKCTF_H
-#define CITEMBACKPACKCTF_H
+
+#pragma once
 
 #include "CItemCTF.h"
 
@@ -30,5 +30,3 @@ class CItemBackpackCTF : public CItemCTF
 
 	int Classify() override;
 };
-
-#endif
diff --git a/dlls/ctf/CItemCTF.h b/dlls/ctf/CItemCTF.h
index da7570de..4cf1b735 100644
--- a/dlls/ctf/CItemCTF.h
+++ b/dlls/ctf/CItemCTF.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CITEMCTF_H
-#define CITEMCTF_H
+
+#pragma once
 
 #include "CTFDefs.h"
 
@@ -58,5 +58,3 @@ class CItemCTF : public CBaseAnimating
 	CTFItem::CTFItem m_iItemFlag;
 	const char* m_pszItemName;
 };
-
-#endif
diff --git a/dlls/ctf/CItemLongJumpCTF.h b/dlls/ctf/CItemLongJumpCTF.h
index 55d2f09b..e7dfd333 100644
--- a/dlls/ctf/CItemLongJumpCTF.h
+++ b/dlls/ctf/CItemLongJumpCTF.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CITEMLONGJUMPCTF_H
-#define CITEMLONGJUMPCTF_H
+
+#pragma once
 
 #include "CItemCTF.h"
 
@@ -30,5 +30,3 @@ class CItemLongJumpCTF : public CItemCTF
 
 	int Classify() override;
 };
-
-#endif
diff --git a/dlls/ctf/CItemPortableHEVCTF.h b/dlls/ctf/CItemPortableHEVCTF.h
index 8e4bf9ce..7954e6bb 100644
--- a/dlls/ctf/CItemPortableHEVCTF.h
+++ b/dlls/ctf/CItemPortableHEVCTF.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CITEMPORTABLEHEVCTF_H
-#define CITEMPORTABLEHEVCTF_H
+
+#pragma once
 
 #include "CItemCTF.h"
 
@@ -30,5 +30,3 @@ class CItemPortableHEVCTF : public CItemCTF
 
 	int Classify() override;
 };
-
-#endif
diff --git a/dlls/ctf/CItemRegenerationCTF.h b/dlls/ctf/CItemRegenerationCTF.h
index d5a9c821..4e9b21ee 100644
--- a/dlls/ctf/CItemRegenerationCTF.h
+++ b/dlls/ctf/CItemRegenerationCTF.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CITEMREGENERATIONCTF_H
-#define CITEMREGENERATIONCTF_H
+
+#pragma once
 
 #include "CItemCTF.h"
 
@@ -30,5 +30,3 @@ class CItemRegenerationCTF : public CItemCTF
 
 	int Classify() override;
 };
-
-#endif
diff --git a/dlls/ctf/CItemSpawnCTF.h b/dlls/ctf/CItemSpawnCTF.h
index c5cb9190..baa0d3ba 100644
--- a/dlls/ctf/CItemSpawnCTF.h
+++ b/dlls/ctf/CItemSpawnCTF.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CITEMSPAWNCTF_H
-#define CITEMSPAWNCTF_H
+
+#pragma once
 
 #include "CTFDefs.h"
 
@@ -24,5 +24,3 @@ class CItemSpawnCTF : public CPointEntity
 
 	CTFTeam team_no;
 };
-
-#endif
diff --git a/dlls/ctf/CTFDefs.h b/dlls/ctf/CTFDefs.h
index a379734e..eccc86b2 100644
--- a/dlls/ctf/CTFDefs.h
+++ b/dlls/ctf/CTFDefs.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CTFDEFS_H
-#define CTFDEFS_H
+
+#pragma once
 
 /**
 *	@file CTF gamemode definitions
@@ -45,5 +45,3 @@ enum CTFItem : unsigned int
 	ItemsMask = LongJump | PortableHEV | Backpack | Acceleration | Unknown | Regeneration
 };
 }
-
-#endif //CTFDEFS_H
diff --git a/dlls/ctf/CTFGoal.h b/dlls/ctf/CTFGoal.h
index 07262ab6..7f49653c 100644
--- a/dlls/ctf/CTFGoal.h
+++ b/dlls/ctf/CTFGoal.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CTFGOAL_H
-#define CTFGOAL_H
+
+#pragma once
 
 class CTFGoal : public CBaseAnimating
 {
@@ -35,5 +35,3 @@ class CTFGoal : public CBaseAnimating
 	Vector m_GoalMin;
 	Vector m_GoalMax;
 };
-
-#endif
\ No newline at end of file
diff --git a/dlls/ctf/CTFGoalBase.h b/dlls/ctf/CTFGoalBase.h
index 1835e4ac..4792a26d 100644
--- a/dlls/ctf/CTFGoalBase.h
+++ b/dlls/ctf/CTFGoalBase.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CTFGOALBASE_H
-#define CTFGOALBASE_H
+
+#pragma once
 
 #include "CTFGoal.h"
 
@@ -28,5 +28,3 @@ class CTFGoalBase : public CTFGoal
 
 	void TurnOnLight(CBasePlayer* pPlayer);
 };
-
-#endif
diff --git a/dlls/ctf/CTFGoalFlag.h b/dlls/ctf/CTFGoalFlag.h
index 166b1c9b..969c88a1 100644
--- a/dlls/ctf/CTFGoalFlag.h
+++ b/dlls/ctf/CTFGoalFlag.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CTFGOALFLAG_H
-#define CTFGOALFLAG_H
+
+#pragma once
 
 #include "CTFGoal.h"
 
@@ -65,5 +65,3 @@ class CTFGoalFlag : public CTFGoal
 	int m_nReturnPlayer;
 	float m_flReturnTime;
 };
-
-#endif
diff --git a/dlls/ctf/CTFSpawn.h b/dlls/ctf/CTFSpawn.h
index 450e2607..cc2533da 100644
--- a/dlls/ctf/CTFSpawn.h
+++ b/dlls/ctf/CTFSpawn.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CTFSPAWN_H
-#define CTFSPAWN_H
+
+#pragma once
 
 #include "CTFDefs.h"
 
@@ -31,6 +31,3 @@ class CTFSpawn : public CBaseEntity
 	CTFTeam team_no;
 	bool m_fState;
 };
-
-
-#endif
diff --git a/dlls/ctf/ctfplay_gamerules.h b/dlls/ctf/ctfplay_gamerules.h
index b10e0f87..ffc55a67 100644
--- a/dlls/ctf/ctfplay_gamerules.h
+++ b/dlls/ctf/ctfplay_gamerules.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef CTFPLAY_GAMERULES_H
-#define CTFPLAY_GAMERULES_H
+
+#pragma once
 
 #include "CTFDefs.h"
 
@@ -140,5 +140,3 @@ void ScatterPlayerCTFPowerups( CBasePlayer* pPlayer );
 void DropPlayerCTFPowerup( CBasePlayer* pPlayer );
 void FlushCTFPowerupTimes();
 void InitItemsForPlayer(CBasePlayer* pPlayer);
-
-#endif
diff --git a/dlls/rope/CElectrifiedWire.h b/dlls/rope/CElectrifiedWire.h
index d6c012d6..d87097b8 100644
--- a/dlls/rope/CElectrifiedWire.h
+++ b/dlls/rope/CElectrifiedWire.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef ROPE_CELECTRIFIEDWIRE_H
-#define ROPE_CELECTRIFIEDWIRE_H
+
+#pragma once
 
 #include "CRope.h"
 
@@ -82,5 +82,3 @@ class CElectrifiedWire : public CRope
 
 	float m_flLastSparkTime;
 };
-
-#endif
diff --git a/dlls/rope/CRope.h b/dlls/rope/CRope.h
index d034316a..64d0c32e 100644
--- a/dlls/rope/CRope.h
+++ b/dlls/rope/CRope.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef GAME_SERVER_ENTITIES_ROPE_CROPE_H
-#define GAME_SERVER_ENTITIES_ROPE_CROPE_H
+
+#pragma once
 
 class CRopeSegment;
 class CRopeSample;
@@ -323,5 +323,3 @@ class CRope : public CBaseDelay
 
 	BOOL m_bMakeSound;
 };
-
-#endif
diff --git a/dlls/rope/CRopeSample.h b/dlls/rope/CRopeSample.h
index 779a8c97..e46a882f 100644
--- a/dlls/rope/CRopeSample.h
+++ b/dlls/rope/CRopeSample.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef ROPE_CROPESAMPLE_H
-#define ROPE_CROPESAMPLE_H
+
+#pragma once
 
 class CRope;
 
@@ -64,5 +64,3 @@ class CRopeSample : public CBaseEntity
 	RopeSampleData m_Data;
 	CRope* m_pMasterRope;
 };
-
-#endif
diff --git a/dlls/rope/CRopeSegment.h b/dlls/rope/CRopeSegment.h
index cb1004b2..43925ccb 100644
--- a/dlls/rope/CRopeSegment.h
+++ b/dlls/rope/CRopeSegment.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef ROPE_CROPESEGMENT_H
-#define ROPE_CROPESEGMENT_H
+
+#pragma once
 
 class CRopeSample;
 
@@ -87,5 +87,3 @@ class CRopeSegment : public CBaseAnimating
 	BOOL m_bCauseDamage;
 	BOOL m_bCanBeGrabbed;
 };
-
-#endif
diff --git a/dlls/weapons/CDisplacer.h b/dlls/weapons/CDisplacer.h
index 4f5ac565..3ef9d59f 100644
--- a/dlls/weapons/CDisplacer.h
+++ b/dlls/weapons/CDisplacer.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CDISPLACER_H
-#define WEAPONS_CDISPLACER_H
+
+#pragma once
 
 enum DisplacerAnim
 {
@@ -95,5 +95,3 @@ class CDisplacer : public CBasePlayerWeapon
 
 	unsigned short m_usFireDisplacer;
 };
-
-#endif
diff --git a/dlls/weapons/CDisplacerBall.h b/dlls/weapons/CDisplacerBall.h
index 5bb5c837..305a6f3f 100644
--- a/dlls/weapons/CDisplacerBall.h
+++ b/dlls/weapons/CDisplacerBall.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CDISPLACERBALL_H
-#define WEAPONS_CDISPLACERBALL_H
+
+#pragma once
 
 class CDisplacerBall : public CBaseEntity
 {
@@ -60,5 +60,3 @@ class CDisplacerBall : public CBaseEntity
 
 	EHANDLE m_hDisplacedTarget;
 };
-
-#endif
\ No newline at end of file
diff --git a/dlls/weapons/CEagle.h b/dlls/weapons/CEagle.h
index 930b83c6..91ab64e5 100644
--- a/dlls/weapons/CEagle.h
+++ b/dlls/weapons/CEagle.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CEAGLE_H
-#define WEAPONS_CEAGLE_H
+
+#pragma once
 
 class CEagleLaser;
 
@@ -92,5 +92,3 @@ class CEagle : public CBasePlayerWeapon
 	BOOL m_bLaserActive;
 	CEagleLaser* m_pLaser;
 };
-
-#endif
diff --git a/dlls/weapons/CEagleLaser.h b/dlls/weapons/CEagleLaser.h
index 599ad3ff..97c2b994 100644
--- a/dlls/weapons/CEagleLaser.h
+++ b/dlls/weapons/CEagleLaser.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CEAGLELASER_H
-#define WEAPONS_CEAGLELASER_H
+
+#pragma once
 
 /**
 *	@brief Identical to CLaserSpot, different class to avoid RPG laser confusion logic. - Solokiller
@@ -25,4 +25,3 @@ class CEagleLaser : public CLaserSpot
 
 	static CEagleLaser* CreateSpot();
 };
-#endif
diff --git a/dlls/weapons/CGrapple.h b/dlls/weapons/CGrapple.h
index d379c843..1222242c 100644
--- a/dlls/weapons/CGrapple.h
+++ b/dlls/weapons/CGrapple.h
@@ -12,8 +12,8 @@
 *   use or distribution of this code by or to any unlicensed person is illegal.
 *
 ****/
-#ifndef WEAPONS_CGRAPPLE_H
-#define WEAPONS_CGRAPPLE_H
+
+#pragma once
 
 class CGrappleTip;
 
@@ -104,5 +104,3 @@ class CGrapple : public CBasePlayerWeapon
 
 	bool m_bMomentaryStuck;
 };
-
-#endif
diff --git a/dlls/weapons/CGrappleTip.h b/dlls/weapons/CGrappleTip.h
index 5276ea0d..9cd035f6 100644
--- a/dlls/weapons/CGrappleTip.h
+++ b/dlls/weapons/CGrappleTip.h
@@ -12,8 +12,8 @@
 *   use or distribution of this code by or to any unlicensed person is illegal.
 *
 ****/
-#ifndef WEAPONS_CGRAPPLETIP_H
-#define WEAPONS_CGRAPPLETIP_H
+
+#pragma once
 
 class CGrappleTip : public CBaseEntity
 {
@@ -65,5 +65,3 @@ class CGrappleTip : public CBaseEntity
 	EHANDLE m_hGrappleTarget;
 	Vector m_vecOriginOffset;
 };
-
-#endif
diff --git a/dlls/weapons/CKnife.h b/dlls/weapons/CKnife.h
index dc1c1656..c27df08f 100644
--- a/dlls/weapons/CKnife.h
+++ b/dlls/weapons/CKnife.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CKNIFE_H
-#define WEAPONS_CKNIFE_H
+
+#pragma once
 
 enum KnifeAnim
 {
@@ -72,5 +72,3 @@ class CKnife : public CBasePlayerWeapon
 	int m_iSwing;
 	TraceResult m_trHit;
 };
-
-#endif
diff --git a/dlls/weapons/CM249.h b/dlls/weapons/CM249.h
index bcbb27ef..9b37c3ae 100644
--- a/dlls/weapons/CM249.h
+++ b/dlls/weapons/CM249.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CM249_H
-#define WEAPONS_CM249_H
+
+#pragma once
 
 enum M249Anim
 {
@@ -91,5 +91,3 @@ class CM249 : public CBasePlayerWeapon
 	float m_flReloadStartTime;
 	float m_flReloadStart;
 };
-
-#endif
diff --git a/dlls/weapons/CPipewrench.h b/dlls/weapons/CPipewrench.h
index d5b9c43d..92bbe57a 100644
--- a/dlls/weapons/CPipewrench.h
+++ b/dlls/weapons/CPipewrench.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CPIPEWRENCH_H
-#define WEAPONS_CPIPEWRENCH_H
+
+#pragma once
 
 enum pipewrench_e
 {
@@ -92,5 +92,3 @@ class CPipewrench : public CBasePlayerWeapon
 private:
 	unsigned short m_usPipewrench;
 };
-
-#endif
diff --git a/dlls/weapons/CShockBeam.h b/dlls/weapons/CShockBeam.h
index 12ca0468..737a3667 100644
--- a/dlls/weapons/CShockBeam.h
+++ b/dlls/weapons/CShockBeam.h
@@ -13,8 +13,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CSHOCKBEAM_H
-#define WEAPONS_CSHOCKBEAM_H
+
+#pragma once
 
 class CShockBeam : public CGrenade
 {
@@ -55,5 +55,3 @@ class CShockBeam : public CGrenade
 
 	int m_iBeams;
 };
-
-#endif
diff --git a/dlls/weapons/CShockRifle.h b/dlls/weapons/CShockRifle.h
index c7d7d355..0f8b217a 100644
--- a/dlls/weapons/CShockRifle.h
+++ b/dlls/weapons/CShockRifle.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CSHOCKRIFLE_H
-#define WEAPONS_CSHOCKRIFLE_H
+
+#pragma once
 
 enum ShockRifleAnim
 {
@@ -84,5 +84,3 @@ class CShockRifle : public CBasePlayerWeapon
 	float m_flRechargeTime;
 	float m_flSoundDelay;
 };
-
-#endif
diff --git a/dlls/weapons/CSniperRifle.h b/dlls/weapons/CSniperRifle.h
index 2c70d05a..bc5e4634 100644
--- a/dlls/weapons/CSniperRifle.h
+++ b/dlls/weapons/CSniperRifle.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CSNIPERRIFLE_H
-#define WEAPONS_CSNIPERRIFLE_H
+
+#pragma once
 
 enum SniperRifleAnim
 {
@@ -83,5 +83,3 @@ class CSniperRifle : public CBasePlayerWeapon
 	BOOL m_bReloading;
 	float m_flReloadStart;
 };
-
-#endif
diff --git a/dlls/weapons/CSpore.h b/dlls/weapons/CSpore.h
index c7475457..215c90ce 100644
--- a/dlls/weapons/CSpore.h
+++ b/dlls/weapons/CSpore.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CSPORE_H
-#define WEAPONS_CSPORE_H
+
+#pragma once
 
 enum SporeAnim
 {
@@ -76,5 +76,3 @@ class CSpore : public CGrenade
 
 	EHANDLE m_hSprite;
 };
-
-#endif
diff --git a/dlls/weapons/CSporeLauncher.h b/dlls/weapons/CSporeLauncher.h
index 88480a96..53365220 100644
--- a/dlls/weapons/CSporeLauncher.h
+++ b/dlls/weapons/CSporeLauncher.h
@@ -12,8 +12,8 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WEAPONS_CSPORELAUNCHER_H
-#define WEAPONS_CSPORELAUNCHER_H
+
+#pragma once
 
 enum SporeLauncherAnim
 {
@@ -94,5 +94,3 @@ class CSporeLauncher : public CBasePlayerWeapon
 
 	float m_flNextReload;
 };
-
-#endif
diff --git a/dlls/world.h b/dlls/world.h
index a4a12c3a..be714255 100644
--- a/dlls/world.h
+++ b/dlls/world.h
@@ -12,13 +12,11 @@
 *   without written permission from Valve LLC.
 *
 ****/
-#ifndef WORLD_H
-#define WORLD_H
+
+#pragma once
 
 #define SF_WORLD_DARK		0x0001		// Fade from black at startup
 #define SF_WORLD_TITLE		0x0002		// Display game title at startup
 #define SF_WORLD_FORCETEAM	0x0004		// Force teams
 #define SF_WORLD_CTF		0x0008		// CTF gamemode
 #define SF_WORLD_COOP		0x0010		// Co-op gamemode
-
-#endif