Kill X-O Arachmech and loot an X-Electro-charged battery. (It's possible that X-O will fall below the terrain on it's death, especially if it's killed in the water, preventing the battery from being looted. If this happens, exit the instance and then re-enter to receive a new battery)
Immobilize Stonerend by killing any three of the four Dark Gears summoners. These necromancers start out non-aggro. Do not cast anything on the named, singular focus is your friend.
Stay clear of the named, wait for a white circle to appear, then run to it and click to place a crystal shard there. Run out, and allow Stonerend to crush the crystals. He will take 20% damage each time, the 5th time you do that the remaining Dark Gear Summoner will attack you, kill him and Stonerend will fall apart.
Fill the phylacteries.
Collect the shattered crystals by clicking on the crushed crystal shards.
Collect the blood from a dead Dark Gears summoner by clicking on it.