diff --git a/mods/ENTITIES/mcl_mobs/api.lua b/mods/ENTITIES/mcl_mobs/api.lua
index 7fee798bc..61976d760 100644
--- a/mods/ENTITIES/mcl_mobs/api.lua
+++ b/mods/ENTITIES/mcl_mobs/api.lua
@@ -393,7 +393,7 @@ local is_node_dangerous = function(self, nodename)
 			return true
 		end
 	end
-	if minetest.registered_nodes[nn].damage_per_second > 0 then
+	if minetest.registered_nodes[nn].damage_per_second and minetest.registered_nodes[nn].damage_per_second > 0 then
 		return true
 	end
 	return false