I beg to differ about having 3 shooter bots for an alliance. Through what I've observed at the regionals I have attended and by watching matches online, sometimes having 3 robots who shoot acts as a disadvantage if the extra robot doesn't have a ball and is stuck playing defense.
The best alliances I've seen usually consist of either 2 placer/shooter bots (preferrably one of each) and one defense bot. HOWEVER having a defense bot also does you no good if all they can do is herd the ball. Having the ability of knocking the ball off the overpass during teleoperated mode is needed. This way the two shooter bots dont have to fuss with removing the balls and once they are down the defense bot basically plays a game of "keep-away". A solid autonomous mode also helps a little bit
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