Describe the crash
I opened up MultiMC today and tried to log into RotN and the game open with the loading screen before going straight to a crash saying that something was wrong with Embassy

To Reproduce
Opened MultiMC
Clicked to Open RotN

Crash Log
https://pastebin.pl/view/5f82a19f

Apologies for not using the link provided in the crash but it failed when I clicked for it to send me the link.

Info (please complete the following information):

• Modpack Version: 2.77.5
• Server or Singleplayer: Either, game will not even open
• Version the world was created on: 2.77.5
  Additional context

Solved.