Games have two different kinds of narratives: Explicit and Emergent. Explicit Narrative is the story that the game tells to the player, and Emergent Narrative is the story the player creates for themselves as they play the game.
Perhaps the most noticeable game featuring Emergent Play is Minecraft, which sold to Microsoft for 2.5 billion dollars. Since then, Sandbox and Survival games have taken off, generating countless titles, almost all of which are Early Access, only a few of which will ever see completion.
Any time you get your player to say: “I Did ______ in [Insert Game Name]” then you have created Emergent Play [EP].
How do you get your player to put themselves in the place of their avatar? How do you encourage them to make decisions and create their own Narrative?