Ted: And so, due to one architectural oversight, the Toledo Bridge Disaster of 1906 claimed the lives of 75 people. [dressed as a hotdog] Now, I hate to stop while I'm on a roll, but happy Halloween, ya crazies!
Scotty: Professor Brosby, you gonna come get beers with us later?
Ted: Nah, I got a thing. But you kids have fun trick or treating.
Betty: This is our treat. You're the coolest, Professor Mosby.
Ted: Well, hot dog.
[later, at a Halloween party:]
Lily: Did it hurt?
Ted: What?
Lily: Getting that kid's nose surgically removed from your ass.
Ted: It's not her nose that's in my ass, Lily, it's her heart. My class loves me. I'm really making an impression on those guys.

Barney: Man, I love the office Halloween party. It is so much sluttier than the office Christmas party. Though not as freaky as the office President's Day Rave. Or the office Tu B'Shvat Pajama Jammy-Jam.

Lily: [on the phone] You just have to learn to embrace their hatred. Because behind that hatred lies fear. And you can use use that fear, like I did with Johnny Marley.
Ted: Was there more to that story?
Lily: A little bit.
[flashback to Johnny Marley waking up from nap time with the stuffed horse's head in his sleeping bag]
Ted: Lily, you're a psychopath.
Lily: A little bit. [to a kid giving Lily her drawing] Aw, a panda!