I find mineshatfs very laggy because hey have A LOT of cave spider spawners. There's so many of them that there's literally over 100 cave spiders even on 4 Simulation Distance. I honestly think there's more cave spider spawners than 19 - 20 etc.
-PS I would show you a picture of the spawners but there's no spectator mode 😛
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-28485.
I think this is likely to be a result of the bug described there. Please add a vote and any new information to the main ticket, which will be updated accordingly.
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