You can carry them, but since they are game pieces you cant carry anything else while doing so;
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GAME PIECES – the TRIANGLE, CIRCLE, SQUARE and UBERTUBE.
HERDING – controlling the movement of a GAME PIECE. A GAME PIECE shall be considered HERDED if it is in contact with the floor and, as the ROBOT moves in the direction of the GAME PIECE, the GAME PIECE is pushed in the same direction in a controlled manner, but does not remain in the position relative to the ROBOT if the ROBOT changes direction or orientation.
<G34> ROBOTS or HOSTBOTS may only POSSESS or HERD one GAME PIECE at a time.