You simply hold down a button, draw ur cursor over the enemies. Release and they die!!! You have to do that to special blocks too that let you advance to the next level. Theres a smart bomb u can use that nukes everyone on screen. Theres bosses that have energy bars and take awhile to kill.It sounds boring and it is IF it didnt have the stunning visuals and sound track that accompanies it! It looks like some sort of wireframe cyberspace thingy and it has various dance/trance tracks.
You need to see it to really understand it tho!