[Thermal]

I do not see anything in the rules that would directly prohibit a team putting a swamp-boat esque shrouded fan powered by a cim on the top of their robot pointing directly up (or at an angle maybe 20 degrees from vertical). A 20" diameter fan powered by 2 cims would be.... scary. Possibly effective, but i'd have to see a prototype. As a hunch though, i'd say it'd be very effective at blocking the middle tier goals, but probably ineffective at changing the path of balls aimed at the top tier goals (unless you're right in front of the robot lobbing for the top rung and can impact the balls motion right as it leaves the robot)