Like many things in this world fire (one of the oldest technologies) can be both a destructive force or a creative one. Every Potter has a love hate relationship with this. None more so then Raku Artists. All pottery must go through the firing processes. This is a traumatic time for every pieces with most making the transition from green-ware to bisque and eventually finished with no problem. Though some have issues or shatter along the way.
With Raku the bisque stage is just the start. Once this happens the artist will decorate the surface and place the piece back into a kiln. However rather then slow heat and cooling the pot is heated rather quickly (often 10-20 min rather then hours) and then snatched out of the still orange/tinted kiln with tongs. It is then either placed in a bin of combustibles and suffocated, or has these combustibles drizzled or poured on it. Many pieces can not withstand this drastic technique, with cracking, chipping, and colors going wrong.
But when the process goes right the effect is magnificent.