Quoted from Pinchroma:There are really only 2 things lit. Blue shots keep the mode alive, red shots end it. 3 red shots and the mode is over. You don't really "Beat" it, you just keep amassing points. The problem is there are MANY more red shots than blue available and they can be hit off ricochets so you need to be careful.
It's a cool mode. I admittedly sometimes like to set the scarecrow on fire on purpose for a laugh