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Mismanor and GrailGM

Mismanor is a role-playing game in which the core mechanic is social interaction instead of combat, with a focus on supporting player-driven story. The story emerges and changes based on the choices the player makes, who they interact with, and how they choose to interact with the other characters. With such a strong focus on social interaction, the game setting was chosen to be a manor party set in 1930s England in which the player character begins to learn and unravel the mystery of the history of the family that owns the manor through interacting and helping the other characters in the game. Mismanor uses two AI systems, CiF  which handles the game level social interactions, and GrailGM which manages the story structure and quest system.

It was necessary to make modifications to the CiF system to work within the role-playing game (RPG) genre. For instance, we needed to add support for items and quest giving, as well as adding the concept and structure for social statistics (stats), similar to typical RPG stats but for a social domain. The player and NPCs each have social stats such as confidence, perception, and persuasion, associated with them, as well as traits, statuses, and relationship networks. This framework is used to help govern what types of interactions are available for each character and the player. We chose to make giving a quest one of the social actions available to the NPCs, allowing CiF to govern the social logic involved with when to assign a quest, while the specifics of what quest to give are left to GrailGM. Finally, Interacting with items uses the same type of logic as interacting with NPCs; depending on the history, player state and world state, different ways of examining, taking, and using items will be available to the player.

The GrailGM layer supports dynamic quest selection as well as story-level author goals. Which quest is chosen to offer to the player is based on story-level authorial goals, the type of quest, past events, traits and statuses of the character the player is talking to, and the relationship between the character and that NPC. Each quest has pre-conditions specifying what type of NPC can give that particular quest, along with what game state is necessary for the quest. A quest has a success state, and a failure state; achieving either state will allow the story to progress in different ways, and have different effects on the state of the world and how the characters view the player. By defining the completion as a state instead of a series of actions that must be performed, the player is able to choose how they complete a quest.

Anne Sullivan, April 2011