Kick from server when use dropstable

The error tells you what the problem is - the item is improperly configured. "388" is an invalid material as of Minecraft 1.13 and above; use the appropriate material name.

Same error with EMERALD or minecraft:emerald :x

Provide new pastes if you're using different files.

https://pastebin.com/89C4BFLt

Your drop table and mob are named the same thing. Don't do that.

Make a minimal reproducible example and provide all the required pastes again. Don't make a paste that has a bunch of other stuff in it, and don't include any unnecessary lines or other content.

https://stackoverflow.com/help/minimal-reproducible-example

You also haven't demonstrated that this is a bug with MythicMobs rather than a configuration issue, so please leave the issue closed until a staff member reopens it.