Sequel to Alcohol's Effect On Friendship!
(Rated for language and humor-based themes.)
Princess Celestia has had enough of Twilight's inebriated letter-writing. So, when Celestia insists that Twilight act as 'designated bar-hopper' for the night, Twilight learns a very important lesson on precisely why ponies should avoid alcohol.

And more importantly, avoid giving alcohol to ancient, immensely powerful princesses who happen to gossip about some fairly embarrassing moments to all of Ponyville.