Yeah it can be quite tricky at times! Yes exactly the more enemies you kill on top of each other, i.e. in one of the circles left behind by an enemy the better reward you get. Just the one enemy that created the circle = health. +1 enemy = minor upgrade. +2 enemies = medium upgrade and so forth! If you manage to get to the room where there are three options where to go next go to the right, there might be some help there :D Thank you very much for trying and I hope it was not too frustrating!