Can't complete quest - Building 793 TWO BIT TOWER

Originally posted by Boxcar Bob: ... they really need to revamp the whole system around clearing. Like have some sort of timer, where if I've been in the mission area and haven't killed any of that mission's zombies for like 5 minutes, give me some indicator to follow.

I like that idea. Olly olly oxen free . It addresses the problem, while if one leaned on this mechanic habitually, they'd just be losing a lot of time before the next Blood Moon.