XT-002 Deconstructor

Tankspot video: http://www.youtube.com/watch?v=BHcFWPUBpr4

(boss tactics write-up by Kachi)

XT-002 Abilities

Gravity Bomb: Charges the target with dark energy, causing them to explode and pull in nearby allies after 9 sec. After 9 seconds, the Gravity Bomb spawns at the player's location: Pulls enemies within 20 (Heroic: 10) yards into a gravity well, dealing 17100 to 18900 (Heroic: 19000 to 21000) damage.
Tympanic Tantrum: Deals damage equal to 10% of each player's maximum health every 1 sec for 12 sec. Nearby enemies are also dazed for the duration. Think Doomwalker's earthquake. One minute cooldown.
Light Bomb: Charges the target with divine energy, causing them to sear nearby allies for 9 sec. The debuff on the targeted player deals 2750 (Heroic: 3500) damage to all enemies within 10 yards of the caster.

Phase 1: Tank and Spank

Note: There is a 6 minute enrage timer on 10-man, and a 6 minute enrage timer on 25-man.
Note2: Rumour goes the enrage timer is increased by 2 minutes if Ignis was killed.
Group makeup
You will need 2 tanks, 2-3 healers, and 5-6 dps. It is strongly advised that all dps have 2800-3500+ dps for the 10 man encounter (if using 5 dps, you will need to average 3500). Any lower and it is most likely that XT will eventually enrage (you will have about 5-10 seconds to continue fighting before all members are dead). Also note that DPS is not constant in this fight, as the heart takes double damage and adds must be taken care off.

Positioning
The boss should be tanked at the top of the stairs, this gives the raid a little bit of extra time to dps the heart before adds are near the boss. Ranged DPS and healers have several choices for positioning:
Many groups try to simply stack, however this increases raid damage significantly.
Alternatively, some choose to designate two groups that are stacked to the left and to the right of the starting area (within healing distance of one another).
Spread the raid out from the boss in a large arc up to maximum distance (35 yards for healers); everyone should be about 6-10 yards apart. Healers need to be spread throughout the raid, and the main healers should be closest to melee. If ranged gets hit with Light Bomb, they do not need to move. If ranged gets hit with Gravity Bomb, they need to move 10 yards away from everyone else to avoid causing additional damage (15 yards to avoid the suction). If melee gets hit with either, they need to run away from the raid towards the north side (the stairs). Make sure you do not suction the Main Tank.
Regardless of where ranged classes stand, everyone should be at least 10 yards away from melee, who should be arranged 360 degrees around XT (since it has no cleave).

Reacting to the debuff
Basically, ranged should only have to deal with ranged characters with the debuffs, and melee should only have to deal with debuffs affecting melee characters. When someone gets hit with Gravity Well or Light Bomb, that person should immediately move away from the group to minimize damage, especially in the case of Gravity Well.

Healers
There needs to be at least two players focused on main healing. Raid healers need to use AOE and direct healing spells whenever Light Bomb appears, or Tympanic Tantrum begins. HoTs are very ineffective at all times unless used on the Main Tank or a healer during Tympanic Tantrum, however AOE heals are more vital during that period of raid wide damage. When Tympanic Tantrum begins, healers need to throw something on themselves quickly, and then begin healing others (preferably AOE heals on themselves and anyone nearby). With enough healers (8 on Heroic), AOE spells that only target members of a specific group tend to be wasted. Single target, direct healing spells and instant cast non-HoTs are the best (Power Word: Shield especially). Players need to pay attention for Tympanic Tantrum and make sure that everyone in the raid gets at least some moderate heals.
Holy Priests should be throwing Circle of Healing on the melee and ranged groups where needed. Prayer of Healing tends to be too slow, but with enough haste can be very effective as well. You should use Power Word: Shield on debuff targets, and Flash Heal should be ready to keep victims of Light Bomb alive.
Druids should HoT themselves and the Main Tank, and use Wild Growth.
Shamans should use Chain Heal on the Main Tank during Tympanic Tantrum.
Holy Paladins are best using Beacon of Light on themselves if healing the Main Tank.

Tympanic Tantrum
During tantrum players will have a daze effect which slows their movement speed by almost half. This ability can be avoided with enough DPS, by revealing the heart before the Tantrum. Latest Blue post stated that "XT-002 Deconstructor will no longer cast Light Bomb or Gravity Bomb while channelling Tympanic Tantrum", which should make this phase easier.
Avoiding the Tantrum
Though complete testing of AoE Avoidance of the various classes has yet to be verified, your standard invulnerability abilities work, though DPS loss in this fight can prove fatal. Also, while Hunter Deterrence is ineffective, Rogue Feint does reduce Tantrum damage in half while the buff is in effect.

Phase 2: Adds

This occurs at 75%, 50%, and 25% health.

Adds
XT-002 will stop attacking and become un-targettable, and begin spawning 3 different types of adds from the junk piles in the 4 corners of the Scrapyard. In addition, he drops his heart which takes 2x damage from players, and the damage is done to the boss as well. Note that there won't be a constant stream of robots.

XS-013 Scrapbots: heals XT-002 for 60k each if they reach him. They need to be AoE'd down and cannot reach the boss for any reason unless killed. They can be stunned, frost nova'd, and knocked back, etc.

XE-321 Boombots: explode upon getting killed, dealing damage to any players or NPCs in range. These have priority and should be single targeted and nuked by ranged. It is best if they are surrounded by scrapbots or near the Heart.

XM-024 Pummelers: standard adds which should be off tanked - Pummelers should never be targeted for DPS as the tight enrage timer does not allow for it.
Off tanks need to be watching for the first Pummelers to appear, which should be picked up and tanked wherever is convenient (near other bots or the boss so that off tanks can help deal damage to either). Have the offtank( hold aggro on them to the sides of the raid. Scrapbots will spawn in small groups of about 5-8. Have people keep an eye out and call out where and when they are coming. When scrapbots get closer to the raid group, they need to be AoE’d down immediately (a Holy Priest using Mind Sear can help reduce the number of DPS wasted on scrapbots). Mages are valuable in that they can nova any of the bots during this phase. Boombots need to be DPS'd when they are near the Heart or scrapbots (or when not near anyone). Melee should stay on the Heart. Note that scrapbot groups can appear simultaneously, and at varying times.
When the heart goes back up into the boss and XT becomes targettable again, unkilled adds will still be alive. Pummelers will need to be offtanked throughout the duration of the entire fight.

The Heart
Health: 10.0M (Heroic), 1.5M (Normal)- Lasts 20 seconds.
Because of the double damage, everyone should be focused on DPSing the boss's heart during this phase (even healers; although priority goes to off tanks and anyone hit by Boombot blasts) as any damage done to the heart is passed along to XT. The raid has a bit of time after the heart drops and before the adds actually start spawning to do so. Healers, if they can spare the mana, should be helping out too because no one in this phase but the off tank (on the Pummelers) should be taking any damage at all. Unless you want to try hard mode, make sure you do not kill the heart. Some raids are able to take the heart down without a bloodlust, in which case everyone has to show restraint to avoid starting Hard Mode. It is possible to defeat XT without having the ability to kill the heart (lack of DPS); however you will still need to average about 1.5M damage per DPS player (4000-6000+ DPS). Bloodlust and all DPS cooldowns should be used on the first adds phase (75% health).
Due to the short enrage for such an encounter, it is imperative that the heart be nuked down to about 5% health. If done so and also managed to kill all the scrapbots to avoid healing the boss. Once the heart phase is over (20 sec.) The boss should have 55 - 60% health, thus the raid can quickly enter phase 2 again, avoiding the tantrums which kills most raids. Try to nuke the heart as much as possible again, of course it won't be as much as last time since cooldowns have been used, but this is the best way to burn his health off quickly!