There is no way to tell, which direction the particle will move at the start, since it has no initial speed. So there is an infinite set of circles it can follow around the first mana bundle.

Edited by author 12.10.2014 03:08

You are wrong.
At the start moment the particle has zero speed, but has non-zero acceleration, which is determine initial movement direction.

Then the description should explicitly state that the force of interaction of the magion with a mana bundle is always directed towards or away from the center of the bundle.

Now the problem statement says that magion at the initial moment moves up.