Obstacles cannot be moved or altered and can sometimes impede your path. These obstacles can do anything to your Flow, from merely changing its color to eliminating it outright. Be advised; obstacles are not always a bad thing. Who knows, you may just find some obstacles to be the greatest assets in your quest for harmony.
Passing through The Divide will cause your Flow to split off in two directions. Which road will lead you to victory?
They say that the shortest distance between two points is a straight line. In Auditorium, that is not always the case. Use the Portal Obstacle to transport your flow to new destinations. Keep in mind, Portals do work both ways...
Nothing is more dangerous to your Flow than the vacuous, hungry void of the Black Hole. Any particles of your Flow that approach it will be sucked in and devoured. Avoid them.
There is more to your Flow than the origin and the destination. The Color of your Flow can and will have to be changed in order to achieve harmony. Passing through a Color Sphere will allow you to change the color of your Flow. At least, until it hits another Color Sphere.