Topic: Exploit of Armor-Repairing Mobs
This was tested on a Mech (Kain Firestorm 1st Star) on the island of New Virginia. There is one lone Mech on the eastern part of the island.
The problem with killing this mech is that its armor repair kicks in around 60%-75% and is impossible to beat with my castel. However, I noticed that if I engage the mob until it starts repairing, then run away until it loses lock, and finally re-engage, it will not attempt to use the armor repair again.
As I have only tested this tactic against this one spawn, I cannot comment as to whether or not it works against other armor repair mobs. However, I am drawn towards the assumption that this is a bug in the AI, rather than with this one particular spawn.