Getting these crashes when using Forge .1225,a custom modpack, and Evilcraft 0.6.1b. This was in singleplayer, and at the time, I was just standing still doing nothing since I wasn't playing. I got 2 crashes at the same time, 1 for the client and another for the server. Since it looks related to the vengeance spirit, I disabled it in the config for the time being. Please look into this when you can, thank you.

Server: http://pastebin.com/3s9hNqAL
Client: http://pastebin.com/mX6ZPgNB

I tried reproducing your crash without luck. I do however have a suspicion what could have caused this issue. Could you try using build 149 (or higher) from here https://drone.io/github.com/rubensworks/EvilCraft/files ? (That version should be stable, only contains this fix among others)

All right, I'll let you know if it happens again since I don't know how to reproduce it myself. Thank you