diff --git a/lua/acf/core/globals.lua b/lua/acf/core/globals.lua
index 754fa1a73..cdba82822 100644
--- a/lua/acf/core/globals.lua
+++ b/lua/acf/core/globals.lua
@@ -67,6 +67,7 @@ do -- ACF global vars
 		npc_strider = true,
 		npc_dog = true,
 		phys_bone_follower = true,
+		acf_armor = not ACF.AllowProcArmor, -- Procedural armor filter
 	}
 
 	-- Ammo
diff --git a/lua/acf/core/utilities/traces_sh.lua b/lua/acf/core/utilities/traces_sh.lua
index e8e347220..25d70022d 100644
--- a/lua/acf/core/utilities/traces_sh.lua
+++ b/lua/acf/core/utilities/traces_sh.lua
@@ -56,7 +56,8 @@ do -- ACF.trace
 
 		util.TraceLine(traceData)
 
-		if Output.HitNonWorld and ACF.CheckClips(Output.Entity, Output.HitPos) then
+		-- Check for clips or to filter this entity
+		if Output.HitNonWorld and (ACF.CheckClips(Output.Entity, Output.HitPos) or ACF.GlobalFilter[Output.Entity:GetClass()]) then
 			local OldFilter = traceData.filter
 			local Filter    = { Output.Entity }
 
diff --git a/lua/acf/core/validation_sv.lua b/lua/acf/core/validation_sv.lua
index c4829afeb..6e4e67240 100644
--- a/lua/acf/core/validation_sv.lua
+++ b/lua/acf/core/validation_sv.lua
@@ -29,7 +29,7 @@ function ACF.IsLegal(Entity)
 
 	local Phys = Entity:GetPhysicsObject()
 
-	if Entity.ACF.PhysObj ~= Phys then
+	if not IsValid(Entity.ACF.PhysObj) or Entity.ACF.PhysObj ~= Phys then
 		if Phys:GetVolume() then
 			Entity.ACF.PhysObj = Phys -- Updated PhysObj
 		else
@@ -196,7 +196,7 @@ function ACF.Check(Entity, ForceUpdate) -- IsValid but for ACF
 		end
 
 		ACF.Activate(Entity)
-	elseif ForceUpdate or Entity.ACF.Mass ~= PhysObj:GetMass() or Entity.ACF.PhysObj ~= PhysObj then
+	elseif ForceUpdate or Entity.ACF.Mass ~= PhysObj:GetMass() or (not IsValid(Entity.ACF.PhysObj) or Entity.ACF.PhysObj ~= PhysObj) then
 		ACF.Activate(Entity, true)
 	end
 
diff --git a/lua/acf/damage/explosion_sv.lua b/lua/acf/damage/explosion_sv.lua
index b24850f16..8153af42c 100644
--- a/lua/acf/damage/explosion_sv.lua
+++ b/lua/acf/damage/explosion_sv.lua
@@ -14,6 +14,7 @@ local TraceData    = {
 	filter = true,
 	mask   = MASK_SOLID,
 }
+local GlobalFilter = ACF.GlobalFilter
 
 --- Checks whether an entity can be affected by ACF explosions.
 -- @param Entity The entity to be checked.
@@ -22,6 +23,7 @@ function Damage.isValidTarget(Entity)
 	local Type = ACF.Check(Entity)
 
 	if not Type then return false end
+	if GlobalFilter[Entity:GetClass()] then return false end
 	if Entity.Exploding then return false end
 	if Type ~= "Squishy" then return true end