The higher the quest tier is, the more zombies spawn. The higher the game stage is, the stronger zombies are.This has been added with A20. It is normal but, as Mounty has already stated, does not happen every single time when the circle gets closer to the burried supply. I get Zombie spawns most of the time, though.
I have also the feeling that with increasing tier of the burried supply quest the more and stronger Zombies spawn. Maybe other factors contribute to that as well (gamestage...).
OSO
SXS
OSO
OSOOO
SXSsO
OSsxs
OOOxs
That's what I've previously been doing and it works well enough. However, it can still take a few seconds to get above ground, depending on how far you're probing underground. The biggest issue on the higher difficulties (and faster zombies) is since our levels are still pretty low (<30), we don't have the armor to really absorb the hits without moving around and potentially exiting the quest area. (Lvl3 Scrap is the best we have atm, with some padded/leather thrown in) Each hit tends to do ~20-25% HP currently. So having 2-3 hostile zombies on top of you almost immediately is a problem, not to mention the possibility of getting infected.How about instead of digging straight down you dig at a slant so you create a natural ramp from the dirt so that way you can get out and ready to fight in about 1 second.......
The circle closes always after X amount of blocks removed, initially 10 I believe. What you can do is dig 9 blocks deep to look for the supplies, get back on surface and dig 1 more random block for the Zs to spawn. You will be instantly ready. If fighting them on foot is too hard place two cobblestone blocks, stand above and hit down on the Zs. OR, even better, use those big rocks that are scattered around randomly in the world. There is a high chance that one of them is inside your quest radius. Or use something else that is elevated, like sheds or fences if the quest is in a town. OR, my favourite, get out your big guns and go BOOM BOOM.That's what I've previously been doing and it works well enough. However, it can still take a few seconds to get above ground, depending on how far you're probing underground. The biggest issue on the higher difficulties (and faster zombies) is since our levels are still pretty low (<30), we don't have the armor to really absorb the hits without moving around and potentially exiting the quest area. (Lvl3 Scrap is the best we have atm, with some padded/leather thrown in) Each hit tends to do ~20-25% HP currently. So having 2-3 hostile zombies on top of you almost immediately is a problem, not to mention the possibility of getting infected.