Corruption and headgear
Effect of headgear on the perception modifier of the "one larger eye" corruption
"Your two front eyes have merged to form one larger eye" gives +4 to Pe, but not if wearing headgear. While this makes a lot of sense for
helmets, helms and
caps, it doesn't make sense for hoods, hats, diadems and crowns (including the artifact crowns). In my opinion only helmets (including the artifact one), helms and caps should negate the Pe bonus.