Looking at the pattern so far, my opponent chose rock in round 1 and paper in round 2, which could suggest progression through the standard rock-paper-scissors sequence. If they continue this pattern, they might choose scissors next. However, they might also anticipate that I'll expect scissors and choose rock to counter. Given these considerations, I'll choose scissors - it would win if they choose paper again (which they might do to break the tie pattern), and if they choose scissors we'll continue the tie streak. This disrupts the previous pattern of my moves (rock, then paper) which makes me less predictable.