[en] Mobile location-aware applications have become quite popular across a range of new areas such as pervasive games and mobile edutainment applications. However it is only recently, that
approaches have been presented which combine gaming and education with mobile Augmented Reality systems. However they typically lack a close crossmedia integration of the surroundings,
and often annotate or extend the environment rather than modifying and altering it.
In this paper we present a mobile outdoor mixed reality game for exploring the history of a city in the spatial and the temporal dimension. We introduce the design and concept of the game and
present a universal mechanism to define and setup multi-modal user interfaces for the game challenges. Finally we discuss the results of the user tests.