New to the forums and this has probably been asked before but what is the deal with my wall attackers being mauled by inferior units. How can 1 peasant ARCHER unit take on 2 spearmen militia units and win??! This makes sieging incredibly hard so what is the problem? Is it this mythical shield bug thing I've been hearing about or what? Or is it the weapon types (spears vs. swords)? Any help offered will be much appreciated.

Thx in advance