Yes. The extra dice will go to the next turret. You roll 7, 15, 20.
One last shot on that turret punches through its weakened armor and strikes something vital as it goes up in flames. Satisfied, you casually place another pair of shots into the next turret over. 20 damage!
Sparnik's men join in again, six shooters per turret, with an extra shooter on the turret you just damaged. Their carbines have trouble getting past that armor, but one of the turrets (which you damaged) is destroyed.
The three remaining turrets, all damaged at various levels, try firing back but roll poorly. Their sensors must have been interrupted by the onslaught of blaster bolts.
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ATTACK ON THE SENSOR ARRAY
Sensor Array- Exterior
Turret x1: 23/12
Turret x1: 11/12
Turret x1: 15/12
Sensor Array- Perimeter
Con: 12/0/12 (cover: 2)
Militia x16: 0/12 (cover: 2)
Militia x9: 0/12
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Pick a target, sir.