Having any Builder's Wand and the Harvest Rod in your inventory at the same time causes a CTD. This only happens in Survival as the items skip some checks in Creative.

Suggest disabling the Harvest Rod and notifying the mod authors.

Found related issue on the Reliquary github.

P3pp3rF1y/Reliquary#619

Latest version (several months ago) appears to include a fix. Can we get this mod updated?

Having the same issue. I can no longer play on my server since this item prevents me from even joining and crashes my game.