Yay! Just downed him and got the green fire. Took all weekend. 2 days of farming the book and a VERY late night for the kill. Thanks for all the awesome advice all. I did a mix of Zum and Zinins techniques.
I set my gate up pretty much where Zum did, but I also put my port a little closer to the alcove so that I could port back into action faster and maintain damage on the boss.
When using pets charge on the boss, precast your Chaosbolt so that you have more time to damage boss during his debuff window.
I stood at pets tail. Used a damage mitigation cd, RoF, FnB Imm, FnB Incin. When they are all out, use pets Fel Breath. They should vaporize.
For Fel hunters:
Use pets Fel Breath and Siphon before sending him off to the other side of the room.
SAVE EMBERS FOR THE DOGS. Demon Soul should be up as well. Have RoF down as they spawn to draw aggro.
Nuke the first one (CB,Con,SB should do it)
Havok the second, Shadowfury to buy time, CB the third and finish them off.
Be ready to port out to LoS CB
For Doom Lord:
Easy. Just be quick with the Banish or let pet tank him
For those who are wiping over and over:
Quick resets are key. Buff and summon/sac as you are running in. Summon boss right away, set up ports during RP. Don't even bother wasting food or pots till you get the mechanics down and are going for the kill shot.
Hang in there. I'm just 496 Item level and mediocre at best. It's a totally scripted fight (no RNG) so you just need to consider what went wrong. Strat? Execution? OMGWTFPANICK? Then adapt and move on.
Thank god he didn't summon a harem of sucubi...