This is how my guild kills Nightmare Kephess. We've downed him three times now, and got our 2 hour titles this week. We use a different strategy from anything else I've seen for the Trandoshan Warriors phase, and it works really well and is super easy. Once we discovered the strategy we use for that phase we have only wiped on that phase one time due to a careless mistake. We actually beat that phase the very first time we tried this strat.
If there are any confusing typos or something that just doesn't make sense let me know. I proofread it, but its pretty long and I may have missed something.
DPS-Gunslinger (Dirty Fighting)
DPS-Gunslinger (Sharp Shooter)
You'll probably want to watch the video and read the guide to get the full idea of whats going on. There is some important stuff going on in the video that you wouldn't really notice just by watching it. Especially during the Trandoshan phase. Also note that in this video we were using our Sage DPS (Balance) instead of our Sentinel. It makes the first phase slightly harder since we only have one person with a short CD interrupt instead of two, but its still quite doable.
Phase 1, the Droids
First, make sure you aren't standing in those purple cones the walker shoots on the ground. They can be in 5 spots, and we creatively call them cone 1, cone 2, cone 3, etc. He will always start on 1, then go in order to 5, then go in reverse order back to 1.
Droid 1 (on your right as you enter)
We have our Shadow tank, our Commando DPS, and our Sage Healer on this one
Droid 2 (the middle one)
Both Gunslingers and our Scoundrel Healer here
Droid 3 (on the left as you enter)
Vanguard tank and Sentinel
Where you put people here matters because of the different CDs on interrupts. Ideally you will have at least 2 people with short CD interrupts (Guardian, VG, and Sentinel). Ideally one of them is a tank as well. For the droid with two people, just switch off every other interrupt. Your CD should be low enough to get all of them. For the other two droids you need a three person rotation (unless you have lots of people with short CD interrupts).
What we do is have our Shadow tank (again, me) and DF Gunslinger be interrupt one. After I interrupt I say "2 is next" on voice. That means that interrupt #2, our Commando DPS and our Scoundrel Healer, will interrupt next. Once they interrupt I say "3 is next" That means our Sage healer and our SS Gunslinger interrupt. Once they do I say "1 is next". Repeat until dead. The middle droid with the 2 DPS on it should die first. They then assist me on Droid one, then once that is dead they switch and kill droid three.
Note for tanks.
I always taunt the middle droid off our Gunslingers after my second interrupt (so the 4th in total). That usually will give me threat on their droid until it dies.
We have everyone gather up right in front of the walker, and I Force Pull the bomber to us. Kill it fast, but don't waste DPS CDs. Once someone gets the bomb they run to the walker to get pulled up. If you have a sage you can pull that person out as soon as the animation goes off (where you shoot that cable up) and avoid all the damage.
The Walker, part 1
Firstly, the Vanguard tank drops his guard, and then I (the Shadow tank) guard him. Yes, you want one tank guarding the other tank. The reason why is for the Warrior phase, which I will explain below.
Blow all DPS on the walker. Pop inspiration, your relics, adrenals, etc. We have our Scoundrel healer and one of our Gunslingers start casting Flyby as soon as the guy with the bomb starts the animation to blow up the walker. The timing works out perfectly so the first flyby tick hits when he becomes vulnerable. Note that you may prefer to save your DPS flybys for the Trandoshan phase, its up to you. If you have a healer, he should definitely use his on the walker, though. Typically we have the walker down to 60-65% here.
The Trandoshan Warrior phase
A voice over effect will play at some point during the Walker phase. This means the Trandoshans are going to spawn soon. We have our Scoundrel healer and our Vanguard tank (again, who is guarded by the Shadow, this is REALLY important) pull the first two warriors out.
At this time we have the Shadow tank and all four DPS sitting behind
the walker. For some reason, the Trenchcutters will always run to a tank, and we ensure that its always the Shadow tank by using guard. If I'm not guarding our Vanguard tank they run for him sometimes instead. That would be bad, and a guaranteed wipe. We are behind the walker so we don't have to worry about the cones. The people in front of the walker, the healers and the VG tank, still need to watch for those.
So now all the Trenchcutters, the Shadow tank, and all the DPS are behind the walker. Kill the Trenchcutters. Healers should be mostly focused on the Trenchcutter tank here, the tank with the two warriors is not going to be taking much damage yet.
Once the first group goes down the people behind the walker sit and wait patiently for the next group. They always charge right at me (Shadow tank). The healers and the Vanguard tank pick off the two warriors again. For some reason it seems like the Warriors are affected by healer aggro but the Trenchcutters aren't. What usually happens is the Trenchcutters go for me, but the Warriors go for healers. They essentially separate themselves. We have the healers and VG try and pick them up just in case, but its not usually needed. Its pretty foolproof.
Note that now the Vanguard has 4 warriors on him and is starting to actually take damage. We have a Gunslinger use their mitigation dome to help out the Shadow tank here, and that's enough for the healers to keep both tanks up.
Group 2 usually dies at the same time group 3 spawns.
Once group 3 spawns, all the Trenchcutters will again run right for the Shadow tank. The Warriors start out targeting me, but healer aggro always pulls them quickly. Again, healer aggro never pulls the Trenchcutters, so they separate naturally. The DPS and I may have to wait a second to start DPS for healers to get aggro on the warriors, but its rare.
People are now taking lots of damage. We use both a Gunslinger dome and my 50% dodge CD behind the walker. The Vanguard now has 6 warriors on him, and he will be using his big CDs here too. The healing here is mainly on the Vanguard. With my dodge CD and a Gunslinger dome I am super tanky.
The DPS should leave one Trenchcutter alive. The bomber won't spawn until the last Trenchcutter dies, and Kephess's enrage timer doesn't start until he is pulled (we think). Once there is just one Trenchcutter up the DPS all leave to clean up the warriors. Once those are all dead we heal up, recover some healer mana, then kill the Trenchcutter and start the second bomber phase.
Same as the first. Once it dies we have the tanks go back to guarding DPS.
2nd Walker phase
Again, same thing, but this time we have all our Smugglers drop flyby preemptively. No reason to save it for the pulsar droids. Also, all ranged DPS and healers should be standing where the first Pulsar Droid spawns so they don't have to move. We usually get the walker to 25%~ here.
Get to the first one as soon as the walker's vulnerability debuff wears off. We keep our Vanguard tank outside of range here so that he eats all the railshots. He also watches the Pulsar Droid that we are not on and gives us a countdown for when we need to switch targets.
This phase is pretty much the same as HM.
We have our Shadow tank (again, me) pick up Kephess and tank him right where he spawns. If you aren't the tank on Kephess, make sure you aren't getting cleaved. Our DPS do some light damage here, but save all their main stuff for the upcoming bomber.
The Vanguard tank pulls it (literally pulls, with Harpoon). Typically the walker will shoot what we call "cone 2" here, so have the bomber tanked in the middle in front of the walker. Move Kephess slightly if there is a potential cleaving problem.
During the bomber Kephess will jump and place a red circle on the ground. You do not want to get hit by it. You actually want to be really far away from it, because after he lands he will pull someone into him and smack them and give them a DoT that ticks for some absurd amount of damage (8k~ I think). Typically he pulls the closest person to him, but its finicky and sometimes pulls someone else thats close. Basically make sure you are far away if you aren't the one who is trying to eat the DoT.
The person eating the DoT should be a Shadow tank. They can use Resilience to completely absorb two ticks of it, which is a lot of damage. After the tank gets the DoT, the other tank needs to leave the bomber and taunt Kephess. Its too much damage for one person to have both the DoT and Kephess on them at the same time. Again, beware of cone 2 here.
Once the bomber dies its on to the final walker phase.
Walker phase 3
Again, maximize DPS here. You won't have the tanks to help DPS here, so everyone really needs to go all out. Don't save CDs for Kephess, use them here. The faster the walker dies the faster you can get DPS back on Kephess, so it has no negative affect on the enrage timer to go all out here. Once its dead, all DPS back to Kephess.
He is still doing that DoT here. We still have the Shadow tank all the DoTs. Resilience won't be back up for the second one, but it should be back up for the third. This is the hardest healing challenge in the fight (heck, the game) so don't be afraid to use healing and tanking CDs here.
The Giant Purple Circle of Doom
After one of the jumps (should be the third one, at around 70-75% HP) we have the tanks pull him to a special spot. You know those ramps by the door where you enter? If you get him in the right spot, you should be able to get the ranged DPS and healers in a position where they can see Kephess and the tanks, but when he pulls them they get caught on that ramp and thus don't have to worry about the giant purple circle of doom.
During the giant purple circle of doom we have the Sentinel use his runspeed buff, have the Sage pull someone out (not the Shadow) and the Shadow uses Force Speed. Gunslingers can use Hunker Down here and ignore the ramps trick.
Once the purple circle of doom is over the fight is basically like HM but with more damage and slightly more hectic purple circle placement by the tanks. He places 5 purple circles per tank swap here. After the 2nd one Kephess will pull the purple circle tank to himself. Just run out so you don't place a circle on the other tank or any melee DPS. Melee DPS and tanks pay attention just in case. Everyone should blow any CDs here as they come up.
The enrage timer is fairly tight, but if you can kill the walker in three phases you should be able to beat it if everyone is playing at the top of their game. There is also an antizerging mechanic here. If at any point more than 1 person is dead he will summon another purple circle of doom, but this one hits for 16k/tick and is basically an instant wipe. So basically don't let anyone die.