Initial 1.16.4 Update! READ ALL
• Added Corail Tombstone
• Removed Corpse (see above)
• Added FTB Essentials
• Removed MA Essentials (see above)
• Added Blood Magic
• Updated All the Mods
• Forge version is 35.0.14
More changes may be found here
If you are coming from 1.16.1 you will need to start a new world
If you are coming from 1.16.2 read here https://github.com/AllTheMods/ATM-6/issues/137
If you are coming from 1.16.3 you should be just fine but I would start a new world.
If you are coming from 1.16.4 you are good to go.
New Worlds will need to restart once to get access to modded dimensions until hopefully next update.
loading into new or existing worlds takes a minute or three so be patient
ALWAYS REMEMBER TO BACKUP BEFORE UPDATING