Mob Farm Question 1.16.4


I’m running a Paper server 1.16.4 and noticed some strange behavior as I was building a monster farm.

When I am standing directly underneath the spawn platform (which is at y-level 199) within 32 block vertical distance (e.g. 30 blocks under the platform), entities spawn on the platform and drop down and die - as it should be. If I am slightly further away (e.g. 34 blocks) entities still seem to spawn above me (looking at the F3 debug output), but the number keeps increasing and only rarely a mob falls down. It seems as if they spawn but then don’t do much.

My hunch was that this has something to do with entity-activation-range, which was originally at 32. But even after increasing it to 64, the behavior does not change. Is this expected to only affect newly created worlds after I change it? On server startup, it reports 64 now for my “standard” world, where the mob farm is located.

I’ve played around with all the mob-spawning settings I could find, but nothing seems to change anything here. Am I missing something? Can someone explain this? I’m out of ideas…

Thanks in advance, have a good 2021,

Not sure if this helps or not. I just created a quick test of 5 minutes at each level.

24 blocks down - 70 mobs with 16 butchered
32 blocks down - 27 mobs with 26 butchered
36 blocks down - 15 mobs with 21 butchered
41 blocks down - 18 mobs with 26 butchered

After each 5 minutes I used /butcher then collected the loot.

This is a brand new server with the mob farm created over the ocean with the spawn platform at 199. No paper settings tweaked.

Guess all it shows is you need to be near 24 blocks away.


Thanks - I guess it confirms my observation somehow.

Just want to clarify: I don’t think this is a spawn issue - monsters seem to spawn quite normal for me even if I am more than 32 blocks under the platforn. But it seems the farm is not working correctly, as they don’t fall down the tower. So another thought I had is: does water flow work normally? Or are the monsters just standing around because the water won’t move them to the center?

I found that there is also a “water” sub-setting for entity-activation-range - but it is at 16 - so if it would have an effect here, it shouldn’t work if I am 30 blocks down from the platform either.