Forge version: 14.23.1.2554
Twilight Forest version: 3.5.246
Link to crash log: https://pastebin.com/dPGVQidB

Steps to reproduce:

1. Place down an anti builder or find one in the ghast tower
2. Place or destroy any block in its radius

What I expected to happen: The game doesn't crash and the anti builder does what it's supposed to do.

What happened instead: The game crashes and upon rejoining, the anti builder did nothing.

Fixed via de6dd19