In FIRST STRONGHOLD, two Alliances of three robots each are on a Quest to breach their opponents’ fortifications, weaken their tower with boulders, and capture the opposing tower. Robots score points by breaching opponents’ defenses and scoring boulders through goals in the opposing tower. During the final 20 seconds of the Quest, robots may surround and scale the opposing tower to capture it. (from firstinspires.org)
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