diff --git a/mods/ENTITIES/mcl_mobs/api.lua b/mods/ENTITIES/mcl_mobs/api.lua
index b9e4c9e63..13206ec6e 100644
--- a/mods/ENTITIES/mcl_mobs/api.lua
+++ b/mods/ENTITIES/mcl_mobs/api.lua
@@ -3593,6 +3593,13 @@ local mob_activate = function(self, staticdata, def, dtime)
 	if not self.nametag then
 		self.nametag = def.nametag
 	end
+	if not self.custom_visual_size then
+		-- Remove saved visual_size on old existing entites.
+		-- Old entities were 3 now it's 1.
+		self.visual_size = nil
+		self.object:set_properties({visual_size = self.visual_size})
+		self.base_size = self.visual_size
+	end
 
 	-- set anything changed above
 	self.object:set_properties(self)
diff --git a/mods/ENTITIES/mcl_mobs/api.txt b/mods/ENTITIES/mcl_mobs/api.txt
index b9b6613b6..b3d414526 100644
--- a/mods/ENTITIES/mcl_mobs/api.txt
+++ b/mods/ENTITIES/mcl_mobs/api.txt
@@ -259,6 +259,7 @@ functions needed for the mob to work properly which contains the following:
 						that are bred in a different way.
 	'pick_up'			table of itemstrings the mob will pick up (e.g. for breeding)
 	'on_pick_up'		function that will be called on item pickup - return true to not pickup the item
+	'custom_visual_size' will not reset visual_size from the base class on reload
 
 	mobs:gopath(self,target,callback_arrived)		pathfind a way to target and run callback on arrival
 
@@ -433,7 +434,7 @@ true the mob will not spawn.
 MineClone 2 extensions
 ----------------------
 
-mobs:spawn_child(pos, mob_type)
+mcl_mobs:spawn_child(pos, mob_type)
 
 This function spawns a mob as a child. The parameter mob_type is the
 entitystring of the new mob.
@@ -443,6 +444,7 @@ mobs:death_effect(pos, collisionbox)
 
 Create death particles at pos with the given collisionbox.
 
+mcl_mobs.spawn(pos,name/entity name)
 
 Making Arrows
 -------------
diff --git a/mods/ENTITIES/mobs_mc/zombie.lua b/mods/ENTITIES/mobs_mc/zombie.lua
index 5ae7e922f..d7c6563b9 100644
--- a/mods/ENTITIES/mobs_mc/zombie.lua
+++ b/mods/ENTITIES/mobs_mc/zombie.lua
@@ -94,13 +94,6 @@ local zombie = {
 	view_range = 16,
 	attack_type = "dogfight",
 	harmed_by_heal = true,
-	on_spawn = function(self)
-		-- Remove saved visual_size on old existing entites.
-		-- Old entities were 3 now it's 1.
-		self.visual_size = nil
-		self.object:set_properties({visual_size = self.visual_size})
-		self.base_size = self.visual_size
-	end,
 	attack_npcs = true,
 }