I have been farming the stones all day for my +15 radiance gear when i came across a new exploit. We even managed to 2 man the 3 bosses with no deaths.
How?
Make sure you have a good healer in your group as this will be needed on the final boss.
Ok make your way to the Hard Mode boss room. Once there make sure the healer does not go into the instance room at all. Let the other members of your group go in the room and start the fight.
The gate will close trapping the healer outside the boss room.(This is how the exploit will work) Once the fight starts pull all 3 bosses to the gate. At either side of the gate you will notice a small gap. These gaps enable the healer to use skill just as long as you are in "line of sight" with the players.
The rest is just simple - Stand in front of the gap in the gate and fight the bosses. The healer just spam's heals and keep you alive as well as pulls agro from the other 1 or 2 bosses.(Don't panic, the bosses can not hit the healer through the gate)
Kill all 3 bosses and loot the cheat to get your stones. You will need 4 stones to barter for the +15 Radiance armour.(The stones from this instance only drop for the leggings on all classes.)
Enjoy and good luck
