Weird white-ish cluster of balloons with purple tint

Hello! So i am new to the game and i just played a match where i saw some new balloons around round 32-33. As the caption says they were white-ish with a slight purple tint to them and they were also in groups of 2-4 on top of eachother. The weirdest thing about them was that they spawned in the middle of the track and they were going the wrong way.

I tried looking to send some of them to the opponent but they weren't there. Does anybody know what they are? I was using dart monkey, canon and wizard as monkeys and quincy as hero if that matters at all.