Blow out, surely that's where no one turns up?
I think (and this is just what I think so feel free to discard what I say but I do this from a position of friendship) if we go out looking for women but don't get any then it might be seen as a let down. Where as if we go out looking for a good time and don't get ladies who cares? If we do bonus!
If this is supposed to be a farewell thing then you might want to save the Apocalypse till the end of the night because what if it's successful?
People will disappear off with random girls and not be around to party.
By all means talk to the ladies, do direct approaches but I wouldn't put so much on it, if we have an awesome night then they will naturally be drawn to us and our energy and our badass costumes (can't I come as a pirate?
).