Teleporting mobs in grinder

[Gabbiman]

Hi everyone, I got a problem, I dont know if this is a feature or bug but as soon as i open
my inventory to AFK at my mob grinder (2 tier5 zombie spawners) Zombies teleport out of the 1x1 collection point
and into my face so they damage me, is this a bug or is it made so you cant AFK nearby them?
BTW it worked yesterday no problem.

 

[TangentialThreat]

So just to be clear, zombies are fully escaping the pen and chasing you? Can we see a picture of the pen?

 

[Gabbiman]

So just to be clear, zombies are fully escaping the pen and chasing you? Can we see a picture of the pen?

They stand in a 1x1 square and are blocked by a slab so the gap is 1,5 blocks. They arnt walking out of there, they just appear.

 

[Gabbiman]

http://imgur.com/wcXQihX

Pic of collection area

 

[TangentialThreat]

There is a well-known vanilla glitch where ghostly mobs at high density appear to teleport through walls, stand there for a few seconds doing nothing and then teleport back - freaky but harmless.

The mobs will be able to hit you from in there sometimes. Go to a .5-block high gap so you're just punching their ankles. That's safer.

 

[Silent_007]

Yeah, I personally wouldn't trust a half slab alone to be enough to really keep a large number of mobs confined to such a small space. Use a full solid block beneath them and see if that helps.

And even then, don't stand too close. You can have a full block between you and the mobs and you'll still be able to hit them. If you're worried about reaching the loot there are plenty of ways to either push it to you or just collect it automatically.