1. Super volcano.
2. An asteroid hits the Earth.
3. All footage of Evel Knievel is lost.
4. Ted calls Karen.
5. Lily gets eaten by a shark.
Lily adds, "I'm Lily, and I approve the order of that list." Hee. She proceeds to tell Barney and Robin the whole story. Ted and Karen were off and on throughout college. They'd be having fun, "douching it up," and then Ted would catch Karen in (his!) bed with some meathead. The meathead would sniff and say, "Sorry, bro," Karen would tell him to read something rather high-brow (e.g. "Before you say anything, I think you should read Baudelaire's Les Fleurs du Mal.") Tu mettrais l'univers entier dans ta ruelle / Femme impure! L'ennui rend ton Ã¢me cruelle. You know? Ted would agree, and then get depressed. After a suitable amount of time had passed, Marshall and Lily would tell them how much they hated Karen. Lily explains: "And then Ted would build up a head of steam and finally take the bus to Providence, to give Karen a piece of his mind." We flash back to Ted arriving back at his dorm room, telling Marshall and Lily that "it" went "great" and then Karen enters the room behind him. Current-day Lily says, "And then sure enough, the whole thing would start all over again." It would and did, right down to a new meathead in Ted's bed with Ted's woman, sniffing "Sorry, bro," at Ted.
Ted tries to play this off as one of those things we all do in college and later live to regret. Personally? I dated a soul-sucking demon for three years. Ask me how! Anyhow, and by way of example, Ted says, "Junior year, Marshall grew a soul patch, wore a Rasta hat, and asked everyone to call him M.J. Smoove.." Marshall says, "I don't regret that for a second." Ted brings the conversation back to himself, confirming that the gang doesn't think he should call Karen. They voice their disapproval loud and clear. Ted then admits to already having called her. Everyone yells at him, although Barney just yells for more of Marshall's pants story. Lily sneers that he might as well ask her to lunch. But Ted says, "I'm not going to ask her out to lunch. Again." Uh-oh. Lily's furious, while Marshall is incredulous. "Why would anyone want to have lunch with their ex?"