Notes:

I know he lost his mind from that bubble, but does he really need to be doing that at this point? The end is kinda going on all around him as he's doing that. Does he mean the end of the end? When the end of the world is finished? And is anyone else suddenly reminded of that one joke from "Cloudy with a chance of Meatballs" where those two guys had different "end is nigh" signs, and the one saying the end is today was laughing at the guy saying the end is tommorow?

Also source: http://gravityfalls.wikia.com/wiki/File:S2e19_the_end_is_nigh.jpg