Use case map traversal against sequence breaking

Sequence Breaking is a type of feature interaction conflict that exists in video games where the player gains access to a portion of a game that should be inaccessible. In such instances, a game's subsuming feature - its storyline - is disrupted, as the predefined set of valid event sequences - events being uninterruptable units of functionality that further the game's story - is not honored, as per the designers' intentions. We postulate that sequence breaking most often arises through bypassing geographic barriers, cheating, and misunderstanding on the player's behalf. In this paper, we present an approach to preventing sequence breaking at run-time with the help of Use Case Maps. We create a narrative manager and traversal algorithm to monitor the player's narrative progress and check the legality of attempted event calls. We verify our solution through test cases and a testing tool, and then show its feasibility through a game we created, concluding that our solution is both sufficient and feasible.