Three crashes, within seconds of starting up.

[Onikrex]

Hey guys, I am trying to play my Hexxit singleplayer and I've crashed 3 times in a row within about 30 seconds of starting up the game. I'm not doing anything special, just crafting some stuff for Tinker's Construct. (Nothing actually using the mod yet, just making the tables and stuff first.)

Edited: After a quick search, I found that it is caused by a turtle boss spawning somewhere. Someone said to go into creative and take him out manually. I went into creative mode and still disconnected within seconds :x