Chain Lightning - Sort of like a Bizarro version of the Shaman spell of the same name, the first target will take no damage while targets after the third jump can be one-shot. Think of a boss version of the Lightning Constructs in the Halls of Stone.
Lightning Nova - Emalon borrows another ability, this time from Loken in the Halls of Lightning. Emalon's version has a five-second cast time, which should be enough time for melee to run the hell away. It has a 20 yard range and should be relatively easy to evade.
Tempest Minion abilities
Overcharged - Emalon chooses one Tempest Minion to Overcharge, which heals that minion to full health. It's a buff that increases its damage dealt by 20% as well as enlarging it. This buff will stack periodically at about 2 second intervals and once it reaches 10 stacks, the Tempest Minion will overload and explode, dealing ridiculous damage in an extremely wide radius that will wipe the raid.
Lightning Nova - In Heroic version, Tempest Minions will also cast a version of Lightning Nova that's weaker than Emalon's but stronger than Loken's. They cast this every 20 seconds.
What to do
The general idea is to get some generous spacing amongst the raid to minimize Chain Lightning damage. Ranged DPS work really well for this fight because they can generally avoid Lightning Novas and switch to an Overcharged Tempest Minion without having to reposition themselves. Melee DPS will have to work a little harder as they keep DPSing Emalon, avoiding the novas, and moving to an Overcharged minion throughout the fight.
There are only two phases to this fight and there is no enrage timer. One tank is required for Emalon and another for the adds, of which there will constantly be four. Whenever a Tempest Minion is killed, Emalon will spawn another one at his location, which means the off-tank should be ready to taunt it to prevent it going after other raid members. Because the off-tank is constantly on the adds, she is generally the one able to spot the Overcharged Tempest Minion the earliest and should be the one to mark it. All DPS should switch (use an /assist macro if you need to) to the minion and kill it before it wipes the raid, which puts low-DPS raids at an extreme disadvantage.
It's essentially shuttling between these two phases and getting into the rhythm of things. If all players -- particularly melee DPS -- manage to stay alive every Lightning Nova cast, and the raid downs Tempest Minions in a timely fashion, Emalon should be a manageable fight.
Normal mode Emalon drops two pieces of loot and Emblems of Valor. He can drop the hands, legs, or chest pieces of Tier 8 (which drop in 10-man Ulduar) and Deadly Gladiator non-set pieces such as the cloak, boots, bracers, rings, and amulets. This gives Emalon a considerably more complex loot table than Archavon. In Heroic mode, he drops four items which can be the hands, legs, or chest pieces of Tier 8.5 (from 25-man Ulduar) or an assortment of Furious Gladiator items, and a pair of Emblems of Conquest. Emalon can drop legs and gloves from the Arena Season 6 sets, as well as any of the non-set pieces making the 25-man loot table even more expansive than the Normal mode. Fortunately, PvP non-set items are not class-specific, which should give players a better chance at winning something. Good luck and have fun storming the
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