Think of Arkanoid or Break-Out on acid, and you have Ghox in a nutshell.
The basic idea of Break-Out type games is that you either break a hole through a brickwall by continously hitting it with a ball of some sort, or destroy all bricks in the wall. So how much easier would it be if you had 20 balls instead of one?
Ghox starts off with 2 balls, picking up green fairies (help pickups are fairies in this game) doubles the number of balls you have, when you die you get a bonus-round of about 20 balls which is activated by a button, but it is so much easier to lose the balls when they are many so the game gets very intense as the number of balls increase. Letting all your balls fall down the screen means you lose a life.
Ghox adds things like moving blocks, end-of-world bosses (make the balls hit the boss to take him out, but some bosses control your balls too... One boss is a soccer goalie, you need to score 1 goal to get past him) and numerous pickups, but in the end it is the same old reliable game..
The background story is something about a great war going on, possibly between a fairytale world and its underworld and you need to seal the underworld or something...