Looking over the previous rounds, the opponent mirrored my moves exactly—with paper, scissors, and rock, all resulting in ties. This suggests they might be using a mirror strategy. Given that any move would likely tie if they continue to mirror, I decided to introduce a slight disruption to the pattern by choosing scissors. If the opponent continues to copy me, we'll tie; however, if they try to anticipate my pattern differently, there’s a chance I might gain an edge. Hence, my move for round 4 is scissors.