Just wanted to thank Braindwen for helping me fullfill my WoW dream of tanking Illidan in Black Temple (the boss that got me into raiding in the first place).
Just wanted to chime in with some additional information for Reliquary Of Souls.
Gear: I was in 475 gear, hit / exp > mastery > crit > haste
Spec: You'll need Nature's Vigil / Incarnation. Renewal is highly recommend
Glyphs: Cat Form / Skull Bash / Savagery
Consumables: I used Flask of Spring Blossoms (Agi flask), Sauteed Carrots (250 agi food) and Virmen's Bite (4000 agi for 20 seconds)
(additional info, my trinkets are Bottle of Infinite Stars (LFR edition) and Zen Alchemist Stone and using Dancing Steel on my weapon. 8557 Proccable Agi)
(This macro saves a fair bit of time, instead of pressing 5 buttons, only pressing 1!)
/cast Tiger's Fury
/cast Nature's vigil
/cast Incarnation: King Of The jungle
/use Virmen's Bite
On Essence of Desire, I Savaged Roared about 2 seconds before she appeared, mangle / mangle / use the above macro / applied dots and Ravage as much as I could. The Spirit Shock is very quick to cast. Be quicker. Rune shield can be easily dpsed through. I ended up having about 10-15% of her health left when she shocked me. Dots finished her off.
Rest of the fight is cake.
Also defeated Alysrazor as Feral. Use the video that Braindwen used in the OP. Clear Lord Rhyoliths trash up to the void walker dude (forgotten his name). He'll run off and no more of that trash will spawn. If you're having issues with healing yourself in the ground phase, use Heart of the Wild to heal yourself up. Will take some attempts to get used to the mechanics of the fight.
Speaking of Lord Rhyolith, using the gear I described earlier, I was able to turn him (In Guardian), however not really knowing the fight, I failed and called it quits after about 5-10 attempts (will need to research the fight some more)
When I was attempting this boss at 85, I had a set of gear that had no gear in it. Then I equiped my normal gear. This brought me down to about 50% health. Just a little tip everyone
Hope this helps someone out in one shape or another!
(Edit: Clarified Lord Rhyolith as being in Guardian spec)