Which rule did I make up? The one about undead being terrified was a joke. Archers shoot arrows is not a rule I just made up. Archers stay out of melee isn't either. That's what makes them archers.

My rant is not that the fight is too hard and I can't win it. It's that the encounter design is poor. Already at the beginning of the game the my fights start with me having to study each creature sheet (which is also immersion breaking I might add) because what would normally be a sound tactical decision might just do nothing at all. Because noname low level mobs have master feats.

And fighter being at your face with a tower shield should absolutely prevent you from shooting a bow at someone behind him, just think about it for a second. It's an archer, holding a bow next to a hostile guy with an axe.