Battle of Dazar'alor
Champion of the LightSingle Target
This is a full single target fight. Make sure to min-max your damage on the boss and dodge the hammers.
You also want to interrupt the adds when they are casting Angelic Renewal.
Grong, the Jungle LordSingle Target / Cleave
Arcane doesn’t really have good cleave and you should focus on full single target here. It’s important to have an interrupt order for the different robots and as a Mage you can easily shimmer towards them if they spawn far away allowing you to reliably do the first one.
On this boss you could consider playing Nether Tempest however it isn’t great since the bosses and adds teleports around a lot. This isn’t Arcane's strongest fight but make sure to not use cooldowns right before there is a lot of movement.
The biggest strength mages have in this fight is that during the maze phase we can easily pick any of the orbs and get to the end of the maze quick to make the phase as easy as possible.
OpulenceSingle Target / AoE
As for the choice of gem, Mages are one of the better classes to take the Topaz gem as we keep stacking the gem even during Flames of Punishment by Ice blocking out side of the raid. By doing this you save your raid the problem of the first set of adds which is usually the hardest one. However, for max damage you want to pick the Emerald gem as you can keep it on high stacks easily by using Shimmer efficiently.
Conclave of the ChosenSingle Target / Cleave
You want to stick to the full single target build here as you don’t really have any useful cleave for this encounter.
Spellstealing the Gift of Wind that Pa’ku casts increases your haste by 45% and movement speed by 75% for 15s. This is really powerful and should be coordinated so that you can always spellsteal it when it’s up. You can also pre Ice block Kimbul’s Wrath which makes you immune to both the initial damage and the bleed debuff.
The most important job on this fight however is that you can dispel curses. Bwonsamdi’s Wrath is a curse that makes a player un-healable and you can only remove this by dispelling it, so make sure to keep your eyes open and help out your raid as much as you can.
King RastakhanSingle Target / Cleave
We play full single target here as well.
You can both blink and Ice block Siegebreaker Roka's Meteor Leap to help the raid avoid taking any damage in the first phase. You can also Ice block off Deathly Withering stacks that you gain from Bwonsamdi’s Aura of Death. Since you are one of the more mobile classes you should never have any trouble with Inevitable End, just make sure to position yourself on open spots by using Shimmer efficiently.
High Tinker MekkatorqueSingle Target
Arcane is really good here as single target is what we are great at and our cooldowns lines up almost perfectly.
Mage's utility is also good on this boss; we can blink the knockup, help others with slow fall, Ice Block off the damage debuffs if you get hit by them and it’s also easy to get behind the pillars using Shimmer. However, it’s important to know that you cannot use Ice Block in the gigavolt radiation zone left behind the explosion of the gigavolt charge (in mythic) as it will still deal damage to you and probably kill you.
Stormwall BlockadeSingle Target / Cleave
This isn’t a very good fight for arcane, because of all the movement. However, it’s still playable and especially during the first phase you can displacement the siren throwing you off the boat and still do great damage.
In the second phase we can blast boss damage or save cooldowns for adds that you have problems with.
Arcane will never be as useful as frost on this boss though because of Frost's slowing capabilities on the adds.
Lady Jaina ProudmooreSingle Target
Same as Mekkatorque, cooldowns line up well and single target damage is good. Arcane is one of the better classes on this boss, especially for last phase because you can do a lot of damage over a short amount of time.
Crucible of Storms
The Restless Cabal2/3 Target Fight
Arcane doesn’t really offer anything special here. You should play the normal single target build and make good use of Shimmer and Displacement to avoid getting hit by Oceanic Essence and the pull-in to put you in bad situations.
As a mage you can Ice Block to remove the Crushing Doubt debuff early to stagger the damage, making it easier for the healers. Greater Invisibility can also be used to keep high stacks of Promises of Power buff for a longer time, but be careful, you do zero damage if you are dead.
It’s also a good idea for a Mage to take the first interrupt on Witness the End as they can easily Shimmer into range and get it without problems, while other classes could have an issue reaching the first one in time.
Uu'natSingle Target / Cleave
Arcane is alright for this boss, we do great single target damage which is the most important damage in this fight. We can Shimmer over the lasers, Ice Block the marks from Unstable Resonance, but make sure to not be in range of others, as it still does damage to everyone within 10 yards of you. It’s also easy to get to the relics to clear your marks using Shimmer and Chrono Shift. But be careful, as of right now, you can’t blink over people with a mark different from you as it will count as a collision.