We examine the use of teleological metareasoning for self-adaptation in game-playing software agents. The goal of our work is to develop an interactive environment in which the game designer generates requirements for a new version of a game, and the legacy software agents from previous versions of the game adapt themselves to the new game requirements in cooperation with the human designer, who provides guidance where automation is not possible or not implemented. We are developing and testing our metareasoning technique for adapting a mature program in the domain of turn-based, multi-player strategy games, specifically FreeCiv (www.freeciv.wikia.com). In this paper, we first present an analysis of adaptations to FreeCiv, next describe our general approach, then describe a specific adaptation scenario, and finally discuss our plans for future work.