Simply yells out "Chaos Bolt to the face!!!!" or "<Player> took my Chaos Bolt to the face!!!" so everyone is aware of how awesome you are.
If the amount is over 100,000 then that will be included in the announcement so everyone knows just exactly how epic you really are.
As of version 1.0.4 it has special messages for when you kill the person with chaos bolt and random messages for various conditions are being added so the addon won't always be just "Chaos Bolt to the face!!!" all the time.