Ask a Bowman Thread.

mace attack is easily avoidable by jumping out of the way, provided you're far enough already to get out before the mace lands. mace also inflicts touch damage sometimes O_o

Yes, the hitbox actually extends when they use the mace. There were a few times over the weekend during the events (on my Hero) that I noticed I PG'd a Guardian, walked past it and could Brandish both the Guardians in front of me and the one hurling its mace at me from behind at the same time. It looked and felt pretty odd. Nexon sure is having a difficult time with hitboxes lately.