Humans have a tendency to consider media devices as social beings. Social agents and artificial opponents can be exam ined as one instance of this effect. With today's technology it is already possible to create artificial agents that are per ceived as socially present. In this paper, we start by iden tifying the factors that influence perceptions of social pres ence in human-agent interactions. By taking these factors into account and by following previously defined guidelines for building

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... ally present artificial opponents, a case study was created in which a social robot plays the Risk board game against three human players. An experiment was performed to ascertain whether the agent created in this case study is perceived as socially present. The experiment suggested that by following the guidelines for creating socially present arti ficial board game opponents, the perceived social presence of users towards the artificial agent improves.