Minecraft version: 1.12.2
Wizardry version: 4.2.7

Question details:
I think I should show you this?

[17:31:27] [Server thread/WARN] [FML]: Electroblob's Wizardry loaded a new chunk [322, 313] in dimension 0 (overworld) while populating chunk [321, 313], causing cascading worldgen lag. [17:31:27] [Server thread/WARN] [FML]: Please report this to the mod's issue tracker. This log can be disabled in the Forge config.

Occasionally this happens because the world generator spills into a new chunk. I managed to remove most of this in the 4.2 update but occasionally it still happens. It's nothing to worry about as long as worldgen isn't being super slow for you. Here's a reddit post about it if you're interested.