In my Minecraft worlds there have been giant holes that just form out of nowhere and cause a TON of lag. Everyone that joins my world (its a LAN world) can see it and are affected by it too. No one can go into it and it just teleports you back to where you were before you tried to go into it. Not only that but about 40 creepers spawn in bulk in the hole and fall into the void. Its literally 40. I've had to delete countless GOOD worlds because of it. Please help!
Added (1). I have tried logging out and back in and they are still there and in the same place. I have also tried going to the nether and back.