As it is right now, when the cruxite artefact is eaten, the new dimension a created, several chuks are loaded, and then on top of it all, a bunch of blocks are moved. This could be improved by creating the dimension as soon as the first item is given to the client, and then one chunk at a time could be loaded each tick. This should be better than doing everything at once.

Okay, actually it's the block transfer that takes the major of the time and not the chunk loading.

Try changing the flags parameter in the setBlock in ItemCruxiteArtifact.makeDestination to 0, so it won't change the changes to the client. It might still work because the player hasn't loaded the world yet when they enter

Hmm. Good point. Didn't think about that.