“CityExplorer is a location-based variant of the popular board game Carcassonne, originally designed by Klaus-Jürgen Wrede (see http://www.carcassonne.de/, German only). A game of Carcassonne always starts with a single tile of the fragmented and hidden game board. Players take turns to draw a new tile and lay it down to extend the city of Carcassonne. Then, they have the choice to place one of their game tokens (followers) on the tile just dropped. Followers can be placed for example on streets, cities or on meadows to control them. A player gets points for the areas their followers hold in control. Once all tiles are laid down, the final scoring takes place. The player with the highest score wins.
CityExplorer adopts the main game idea of Carcassone and relocates the game play in the real world via GPS technology. It can be played anywhere in the world by a theoretically infinite number of players. The game consists of an online component and a real-world offline component.
The goal of the game is to seize the most of real-world locations in the explored real-world game area by placing virtual “followers”, so called tokens, to them. As hinted by the name “CityExplorer”, the game is designed to be played in a city. Placing tokens is only valid on predefined types of real-world locations, as in the original. For example, players are allowed to place their followers only to churches or beer gardens found in the game area.
The online component of the game (www.kinf.wiai.uni-bamberg.de/cityexplorer/) handles the game and player management. After registration, players can start new games or join existing ones in any region of the world. Before a round of CityExplorer, the players choose the set of real-world locations game tokens are allowed to be placed to. This online pre-game phase is necessary to guarantee fairness. Some players may know the position of beer gardens better than others, who in return may have visited a few more churches recently. To balance such different knowledge levels, players are asked to choose an equal amount of preferred real world locations.
After all players have chosen their preferred location types and agreed with the play time, they download the mobile client on their GPS-capable mobile device with photo camera and can start exploring. To set a virtual token on the real-world game board, they must take a representative photo of the location they placed their token to. Since the game-relevant locations are not known before the game, the verification of set locations cannot be automated by the game software. All set tokens are to be uploaded to the online management platform. The players judge the correctness of the token placement of each other manually by reviewing the corresponding photos. If a token is judged to be wrong by one player, the owner of the token has the possibility to adjust the token – the coordinates, the location type as well as the photo – and get it count in the final scoring, as long as the game goes on.
To add strategic depth to the game play and simulate the tile-based game board of the original, the real-world game board is divided in different regions. Players explore these regions and place their tokens on valid locations within them. The player who holds the majority of tokens in such a region claims the domination of it and gets points for it at the end of the game. Additionally, players get points for placing the most tokens to one valid type of locations on the entire game board.
When the game time is over, which can vary from one day to several months – just as the players who started the game round chose – the player who has gathered the most points wins. As the game play is kept relatively simple, the game can be played during a walk in the park, during a shopping tour or on the way home from work.” (1)
(1) Matyas, S., Matyas, C., Mitarai, H., Kamata, M., Kiefer, P ., and Schlieder, C. (2009), Designing Location-based Mobile Games – The CityExplorer Use Case, In: Digital Cityscapes: Merging Digital and Urban Playspaces, (eds.) Adriana de Souza e Silva and Daniel M. Sutko, Peter Lang Publishers, NY, ISBN 978-1-4331-0532-6, pp. 187-203.