diff --git a/src/info.cpp b/src/info.cpp
index 81912150b..84d8e26be 100644
--- a/src/info.cpp
+++ b/src/info.cpp
@@ -257,6 +257,7 @@ PClassActor::PClassActor()
 	WoundHealth = 6;
 	FastSpeed = -1.;
 	RDFactor = 1.;
+	SelfDamageFactor = 1.;
 	CameraHeight = INT_MIN;
 
 	DropItems = NULL;
@@ -317,6 +318,7 @@ void PClassActor::DeriveData(PClass *newclass)
 	newa->WoundHealth = WoundHealth;
 	newa->FastSpeed = FastSpeed;
 	newa->RDFactor = RDFactor;
+	newa->SelfDamageFactor = SelfDamageFactor;
 	newa->CameraHeight = CameraHeight;
 	newa->HowlSound = HowlSound;
 	newa->BloodType = BloodType;
diff --git a/src/info.h b/src/info.h
index 50db1e4b6..a9f79182f 100644
--- a/src/info.h
+++ b/src/info.h
@@ -299,6 +299,7 @@ public:
 	int WoundHealth;		// Health needed to enter wound state
 	double FastSpeed;		// speed in fast mode
 	double RDFactor;		// Radius damage factor
+	double SelfDamageFactor;
 	double CameraHeight;	// Height of camera when used as such
 	FSoundID HowlSound;		// Sound being played when electrocuted or poisoned
 	FName BloodType;		// Blood replacement type
diff --git a/src/p_interaction.cpp b/src/p_interaction.cpp
index 38d9cd375..4c23c8123 100644
--- a/src/p_interaction.cpp
+++ b/src/p_interaction.cpp
@@ -1020,6 +1020,11 @@ static int DamageMobj (AActor *target, AActor *inflictor, AActor *source, int da
 		}
 		return 0;
 	}
+	if (target == source && damage < TELEFRAG_DAMAGE)
+	{
+		damage = int(damage * target->GetClass()->SelfDamageFactor);
+	}
+
 	// [MC] Changed it to check rawdamage here for consistency, even though that doesn't actually do anything
 	// different here. At any rate, invulnerable is being checked before type factoring, which is then being 
 	// checked by player cheats/invul/buddha followed by monster buddha. This is inconsistent. Don't let the 
diff --git a/src/p_mobj.cpp b/src/p_mobj.cpp
index dfb0c7312..f85f2c9eb 100644
--- a/src/p_mobj.cpp
+++ b/src/p_mobj.cpp
@@ -321,6 +321,7 @@ DEFINE_FIELD(PClassActor, GibHealth)
 DEFINE_FIELD(PClassActor, WoundHealth)
 DEFINE_FIELD(PClassActor, FastSpeed)
 DEFINE_FIELD(PClassActor, RDFactor)
+DEFINE_FIELD(PClassActor, SelfDamageFactor)
 DEFINE_FIELD(PClassActor, CameraHeight)
 DEFINE_FIELD(PClassActor, HowlSound)
 DEFINE_FIELD(PClassActor, BloodType)
diff --git a/src/scripting/thingdef_properties.cpp b/src/scripting/thingdef_properties.cpp
index 50b81310c..6537e2482 100644
--- a/src/scripting/thingdef_properties.cpp
+++ b/src/scripting/thingdef_properties.cpp
@@ -1430,6 +1430,16 @@ DEFINE_PROPERTY(radiusdamagefactor, F, Actor)
 	static_cast<PClassActor *>(info)->RDFactor = i;
 }
 
+//==========================================================================
+//
+//==========================================================================
+DEFINE_PROPERTY(selfdamagefactor, F, Actor)
+{
+	PROP_DOUBLE_PARM(i, 0);
+	assert(info->IsKindOf(RUNTIME_CLASS(PClassActor)));
+	static_cast<PClassActor *>(info)->SelfDamageFactor = i;
+}
+
 //==========================================================================
 //
 //==========================================================================