The goal of this research was to investigate how changes in modality (communication type) and external conditioning (warnings of player deception) relate to perceptions of deception and task difficulty and, in turn, how these perceptions relate to the final group game scores in a cooperative effort with conflicting goals. One hundred and eight participants were grouped into teams of three, given similar instructions but different goals, and asked to play a cooperative game called StrikeCOM that simulates the intelligence gathering needed to develop an air tasking order and subsequent air strike on three military targets. The analysis of the post-game surveys showed support for participants in games using a face-to-face communication method to have lower perceptions of deception and task difficulty when compared to games using real-time plain text chat.