diff --git a/Generals/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h b/Generals/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h
index 17d2a95021e..790a10edbd7 100644
--- a/Generals/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h
+++ b/Generals/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h
@@ -91,5 +91,10 @@ class PoisonedBehavior : public UpdateModule,
 	Real					m_poisonDamageAmount;
 	ObjectID			m_poisonSource;
 	DeathType			m_deathType;
+	// TheSuperHackers @bugfix ZsoltFeher 07/20/2026 Reentrancy guard so our own periodic poison
+	// damage-over-time tick (see update()) does not re-trigger onDamage() on ourselves now that
+	// it deals real POISON damage. damage.in.m_sourceID cannot be used for this since it is set
+	// to the original poisoner (for XP credit), which could legitimately re-poison us again.
+	Bool					m_dealingPeriodicDamage;
 
 };
diff --git a/Generals/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp b/Generals/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp
index 5483e20dd84..a476c883067 100644
--- a/Generals/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp
+++ b/Generals/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp
@@ -72,6 +72,7 @@ PoisonedBehavior::PoisonedBehavior( Thing *thing, const ModuleData* moduleData )
 	m_poisonDamageAmount = 0.0f;
 	m_poisonSource = INVALID_ID;
 	m_deathType = DEATH_POISONED;
+	m_dealingPeriodicDamage = FALSE;
 	setWakeFrame(getObject(), UPDATE_SLEEP_FOREVER);
 }
 
@@ -87,7 +88,16 @@ PoisonedBehavior::~PoisonedBehavior()
 void PoisonedBehavior::onDamage( DamageInfo *damageInfo )
 {
 	if( damageInfo->in.m_damageType == DAMAGE_POISON )
+	{
+#if !RETAIL_COMPATIBLE_CRC
+		// TheSuperHackers @bugfix ZsoltFeher 07/20/2026 Our own periodic poison damage-over-time tick
+		// (see update()) now deals real POISON damage so that POISON resistance applies to it. Ignore
+		// it here so it does not re-arm/re-trigger this same PoisonedBehavior instance on ourselves.
+		if( m_dealingPeriodicDamage )
+			return;
+#endif
 		startPoisonedEffects( damageInfo );
+	}
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -119,9 +129,23 @@ UpdateSleepTime PoisonedBehavior::update()
 		DamageInfo damage;
 		damage.in.m_amount = m_poisonDamageAmount;
 		damage.in.m_sourceID = m_poisonSource;
+#if RETAIL_COMPATIBLE_CRC
 		damage.in.m_damageType = DAMAGE_UNRESISTABLE; // Not poison, as that will infect us again
+#else
+		// TheSuperHackers @bugfix ZsoltFeher 07/20/2026 Deal actual POISON damage on the periodic tick
+		// so the target's POISON resistance (e.g. Chemical Suits) is properly applied. This used to be
+		// UNRESISTABLE to avoid re-triggering ourselves; onDamage() now guards against that explicitly
+		// via the m_dealingPeriodicDamage reentrancy flag instead.
+		damage.in.m_damageType = DAMAGE_POISON;
+#endif
 		damage.in.m_deathType = m_deathType;
+#if !RETAIL_COMPATIBLE_CRC
+		m_dealingPeriodicDamage = TRUE;
+#endif
 		getObject()->attemptDamage( &damage );
+#if !RETAIL_COMPATIBLE_CRC
+		m_dealingPeriodicDamage = FALSE;
+#endif
 
 		m_poisonDamageFrame = now + d->m_poisonDamageIntervalData;
 	}
diff --git a/GeneralsMD/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h b/GeneralsMD/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h
index 5897092528a..aba56d52137 100644
--- a/GeneralsMD/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h
+++ b/GeneralsMD/Code/GameEngine/Include/GameLogic/Module/PoisonedBehavior.h
@@ -91,5 +91,10 @@ class PoisonedBehavior : public UpdateModule,
 	Real					m_poisonDamageAmount;
 	ObjectID			m_poisonSource;
 	DeathType			m_deathType;
+	// TheSuperHackers @bugfix ZsoltFeher 07/20/2026 Reentrancy guard so our own periodic poison
+	// damage-over-time tick (see update()) does not re-trigger onDamage() on ourselves now that
+	// it deals real POISON damage. damage.in.m_sourceID cannot be used for this since it is set
+	// to the original poisoner (for XP credit), which could legitimately re-poison us again.
+	Bool					m_dealingPeriodicDamage;
 
 };
diff --git a/GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp b/GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp
index 1cadfe55df4..225f328dd0e 100644
--- a/GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp
+++ b/GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Behavior/PoisonedBehavior.cpp
@@ -72,6 +72,7 @@ PoisonedBehavior::PoisonedBehavior( Thing *thing, const ModuleData* moduleData )
 	m_poisonDamageAmount = 0.0f;
 	m_poisonSource = INVALID_ID;
 	m_deathType = DEATH_POISONED;
+	m_dealingPeriodicDamage = FALSE;
 	setWakeFrame(getObject(), UPDATE_SLEEP_FOREVER);
 }
 
@@ -87,7 +88,16 @@ PoisonedBehavior::~PoisonedBehavior()
 void PoisonedBehavior::onDamage( DamageInfo *damageInfo )
 {
 	if( damageInfo->in.m_damageType == DAMAGE_POISON )
+	{
+#if !RETAIL_COMPATIBLE_CRC
+		// TheSuperHackers @bugfix ZsoltFeher 07/20/2026 Our own periodic poison damage-over-time tick
+		// (see update()) now deals real POISON damage so that POISON resistance applies to it. Ignore
+		// it here so it does not re-arm/re-trigger this same PoisonedBehavior instance on ourselves.
+		if( m_dealingPeriodicDamage )
+			return;
+#endif
 		startPoisonedEffects( damageInfo );
+	}
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -119,10 +129,24 @@ UpdateSleepTime PoisonedBehavior::update()
 		DamageInfo damage;
 		damage.in.m_amount = m_poisonDamageAmount;
 		damage.in.m_sourceID = m_poisonSource;
+#if RETAIL_COMPATIBLE_CRC
 		damage.in.m_damageType = DAMAGE_UNRESISTABLE; // Not poison, as that will infect us again
+#else
+		// TheSuperHackers @bugfix ZsoltFeher 07/20/2026 Deal actual POISON damage on the periodic tick
+		// so the target's POISON resistance (e.g. Chemical Suits) is properly applied. This used to be
+		// UNRESISTABLE to avoid re-triggering ourselves; onDamage() now guards against that explicitly
+		// via the m_dealingPeriodicDamage reentrancy flag instead.
+		damage.in.m_damageType = DAMAGE_POISON;
+#endif
 		damage.in.m_damageFXOverride = DAMAGE_POISON; // but this will ensure that the right effect is played
 		damage.in.m_deathType = m_deathType;
+#if !RETAIL_COMPATIBLE_CRC
+		m_dealingPeriodicDamage = TRUE;
+#endif
 		getObject()->attemptDamage( &damage );
+#if !RETAIL_COMPATIBLE_CRC
+		m_dealingPeriodicDamage = FALSE;
+#endif
 
 		m_poisonDamageFrame = now + d->m_poisonDamageIntervalData;
 	}