This is the third to the last form of a quest to upgrade the Relic Knuckles into the ultimate hand to hand weapon, the Spharai. The second to the last form allows you to use the ultimate H2H WS "Final Heaven," but only in Dynamis. The Final form allows you to use it anywhere.
No one knows how powerful the ultimate WS are, as no one is known to obtained them.
this i believe is the second stage of sephari modification you need to do it four time before get the ult. weapon foor mnk for more info look up relic knuckles read the threads there adn related threads it will help you alot it helped me