Apply the diamond powder to the weak points of the Nak'azar titan in Chardok (this is the big statue directly across from the second sokokar post). This can be done on the back of his legs.
Harvest "a Di'Zokian blasting keg" ( -480, -84, -333 ) /waypoint -480, -84, -333 that is in The Water Chamber along the wall. Place it between the titan's feet for update (you get an info window when you mouse over it). All group members must do this at the same time in order to get the next update. If you don't you'll need to go back and get another keg to place (wait ~10 minutes if this is the case).
When the keg explodes 5 heroic titan shard's (level 79^) will pop. Kill them for update.