How to write an opening line people answer
A strong opening sets the place, the voice, and one unfinished beat in a few sentences.
Start inside the room
Name a sensory detail the other person could notice: rain on a coat, a cup that has gone cold, a door that was left open. Then give the character one line of speech or one action that asks for a response. The reader should be able to answer without reading a prologue.
Match the storyline title. If the card says a night market and the opening is a throne room, the public page and the chat feel like two products.
Leave the biography out of sentence one
Age, faction, tragic past, and a list of powers can wait until they change the scene. The opening only needs the tension that is happening now: an unpaid debt, a missed train, a question the character is afraid to finish.
Two to five sentences is enough for a 1:1 storyline. Longer openings hide the place where the other person is supposed to speak.
Ensembles need a shared room first
A group opening is narration, not one character's monologue. Seat the cast: who is present, what just happened, and what the player can do next. Spoken lines come after that, so the first reply is not forced to explain the whole table.