i just played/finished my first round of the zombies mode, holy shit was that boring. just pick blade and constantly upgrade your sword attack damage/speed, you can just stand in a crowd and hold attack. I had 888k damage, next highest player only had like 300k.
this is really discouraging for me, since i hoped they would one day add a fun PVE mode - now i feel like they might not ever be able to figure that out.