Re: Star Trek: Destiny Book 3: Lost Souls - (SPOILERS)
^^Yeah, but then they brought it back, so that doesn't count.
However, there have been books in which entire other universes or parallel timelines were extinguished permanently. Heck, at the beginning of Q&A, Keith describes the wholesale annihilation of several universes. That's pretty hard to beat.
you are all little too bloodthirsty, aren't you?
"A person without any sense of shame is no longer a human being."
Mencius, Chinese Philosopher (c. 372-289 BCE)