I got this guide from http://youtu.be/oYIedfHmFwk (MyrkridianTV on youtube) and modified it a little.
With this guide, you’ll get infinite furry, shots that go through shadows, the ability to cripple/bleed/increase incoming damage to Liadri, and make the fight easy.
Food:
1) Bowl of Meat and Winter Vegetable Stew (+30% Endurance regeneration)
2) Master Maintenance Oil
You can use the higher version Bowl of Orrian Truffle and Meat Stew but it’s double the price for only 10% more endurance regen. You must use these.
http://wiki.guildwars2.com/wiki/Food#Might_on_Dodge
Traits:
0/30/20/20/0
Arms: II VII IX Defense: II IV Tactics: I VII >>MUST USE OR GUIDE WILL NOT WORK<< Only thing you can touch is the 5 points after defence 15.
Skills:
Healing Signet, Stamina Signet, shake it off, endure pain, signet of rage (Don’t use burst skills because defence 15 grants more health regen at max adrenaline).
Armor/weapons:
Full berserker gear with ruby orbs with a melee weapon to kill the first orb only then switch to rifle after the 1st phase is done. I used a superior sigil of accuracy in the berserker rifle.
Guide:
You will spawn somewhere in the cage, you must kill the orb fast. Using a warhorn for speed boost and vigor could help at the first stage but I did not go that route, I went with the greatsword. Drag the shadow figures into the light to make them crystals then immediately just run on top of Liadri and toss it at her.
Take the safe route and don’t be risky, meaning don’t dodge inside the red rings because one mistake and you’re done. I used whirlwind attack to rush out of danger and dodged. Three crystals tossed at her and she will begin attacking you and now the fun begins!
Second phase:
Switch to rifle immediately and never switch back to your other weapon(s).
With the traits I posted, the recharge rate of cripple will be 8 seconds and will immobilize her along with giving you furry. Use skill 2 (cripple, immobilize) then brutal shot (-8% to her) then volley and just spam 1 while watching the floor avoiding insta-death rings. Also wait a extra 2 seconds with aimed shot (skill 2) so the trait furry will kick in when you immobilize her again. Try to stay near the middle, if you go to far off you might waste endurance trying to dodge then die.
If you get pulled use rifle butt to kill the orb and dodge away if you need to.
Use shake it off just incase if you get crippled and the trait line shake it off only removed weakness.
Use endure pain if Liadri just jumps you and you can’t get away fast enough.
All you have to do is keep Liadri targeted and with crack shot (VII) everything will just pass through the shadows and hit her as well.
Practice makes perfect, and good luck!
(Picture below also of traits)
