After the latest patch I’ve noticed that sometimes rounds of Zombie Massacre won’t continue past the “WARNING: INCOMING WAVE” phase. I’ve had this happen 3 times (twice on Day 1 and once on Day 2), in official and workshop maps.
I’m not sure if there’s a specific way to replicate this. It seems to be random when it happens.
Are you opening the pause menu?
I don’t consciously remember doing that, but I just tried pausing the game while the “INCOMING WAVE” pop-up was on-screen and that caused the bug to happen every time, so I probably did that and just forgot.
After testing the pause feature a bit more it seems like the bug is actually just that unpausing isn’t resuming timers (and zombie spawners). If I pause and unpause after a round starts, the timer on the HUD hides and zombies stop spawning.