So, what is Particle Illusion? Simply put, its a tool you use post recording of video to add effects to you videos. So for example, say you wanted to add a fireball being thrown through your video or an explosion. This is the tool to allow you to do that.
Infact, it allows you to enter so many effects you just wouldn't have been able to do in production of video.
So, in a nutshell, if you interested ietails adding effects to you videos then this is the tool for that.