Its the same for me, but it doesnt matter what level of the creeps. And it seems like its random, cos sometimes it hits sometimes it doesnt. Very annoying.Actually, I seemed to have something like that... On Burna Boy (the Incinerate build)... Whenever I shot at a creep, it seemed to do no damage until melee range. Then, when they get into melee range, they just go BOOM!.
Except, that's only in mid-late game creeps. Early game creeps seem to take damage fine.
Btw, great map. I host it like 2 times a day, but thers not a huge rush of people joining, maybe time for a new version?