Romance: Must Contain: Twilight, Future Twilight, Twilight's library.
Sad: Must Contain: Tank, Rainbow Dash, Gilda, Pet-napping.
Tragedy: Must Contain: Scootaloo, Rainbow Dash, Timber-wolves.
Dark: Must Contain: Nightmare Moon, Pipsqueak, Nightmare Night.
Comedy: Must Contain: Big Mac, Zecora, Smarty Pants Doll.
Random: Must Contain: Derpy, Princess Luna, Cloudsdale.
Adventure: Must Contain: Doctor Whooves, Lyra Heartstrings.
Slice of Life: Must Contain: Carrot Top, Roseluck, Canterlot, Competition.
Crossover: Must Contain: CMC, Pinkie Pie, Winnie the Pooh.
Alternate Universe: Must Contain: Spike, Gilda, Rainbow Dash
Human: Must Contain: Trixie, Detrot.

A few differences. I've put a couple of scenarios in challenges to help those struggling to think of some.

On the Human one, what's Detrot? It doesn't terribly matter, because I'm doing the Random one, but still I'm curious.

EDIT: Never mind, I'm retarded. It's the pony version of Detroit, isn't it?