Watabou's "Teen Island Simulator" is a text-based simulation of a pencil and paper role-playing game called "Teen Island" by Chris McDowall.

Basically it plays the game by itself and you watch the situations all play out. It plays in both mobile and desktop browsers:

watabou.itch.io/teen-island-si

Also if you haven't seen Watabou's generators for dungeons, medieval fantasy cities, and mansions, check them out:

watabou.itch.io/