While there are 3 mini-bosses to kill in Ruby Sanctum before engaging Halion, there's really nothing special to these encounters. Use Holy Light on the tanks, a lot, and you'll be fine. Note that some of the bosses and even some of the trash can hit pretty hard, this isn't as easy as a walk through Sartharion's Lair. You'll want to stick to your Holy Lights, especially on Baltharus, as he likes to kill tanks when unsuspecting healers aren't watching. Each mini-boss fight is very short, and you'll be ready to engage Halion in no time.
Halion the Twilight Destroyer
No, unfortunately Halion was not sent to destroy all things related to the Twilight series. He's here to steal some red dragon eggs for his boss, Deathwing. We're going to stop him. The fight has three phases, and our role changes based on which phase we're currently in. He's a relatively hard-hitting dragon, and so we'll be spending most of our time healing the tanks and then spot-healing any members of the raid that could use our help.
The first phase of Halion plays much like a mix of Sartharion and Grobbulus. Halion is a dragon, and as I'm sure you've guessed, he's got a powerful tail swipe, frontal cleave, and Flame Breath. You'll want to stay on one of the dragon's sides, avoiding the aforementioned attacks. For the most part, this is Halion in phase 1. He will occasionally target a patch of ground underneath a player for a Meteor Strike, which will explode and there will be a few runners of fire, similar to Lord Marrowgar's Coldflames. Just avoid the ground zero of the Meteor Strike, and then make sure you're not standing in flames. Make sure you have Beacon of Light on the single tank, and just heal whoever takes damage. Pretty easy, right?
Of course, there is one more mechanic that makes this phase a bit more interesting. Fiery Combustion is a new type of debuff-a hybrid between a curse and a magic affliction. It can be cured by either type of dispel, so we can actually remove it using Cleanse. However, this debuff is basically a mix of a void zone and a Grobbulus disease, and so where we dispel it is key. You'll want for the afflicted member to run away from the raid, and then we'll dispel them immediately. They'll explode, and also drop a void zone of fire that is proportional in size to how long they had the debuff. If they had it for a long time, the explosion will be huge, and it will hurt and knock back anyone nearby. It's important that debuffed players run away fast, and that we dispel them as soon as they're in position. Obviously you'll want to stay out of this fire on the ground too. On heroic mode, standing in the fire also puts a DoT and a slow on you, so make sure you're out of the fire immediately.
At 75%, Halion will hop into his twilight portal and hide in the twilight realm. We'll hop in after him by right-clicking the portal that he spawns. Let your tank go in first, since he'll want to reposition Halion once inside. Now that you're in the twilight realm, you'll continue battling Halion in much the same way. He's still a dragon, and so you'll want to again avoid his front and rear conical abilities. Many guilds will switch tanks at this point, so make sure your Beacon and Sacred Shield are on the proper targets.
The defining difference between the physical realm and the twilight realm is the presence of a pulsing shadow aura called Dusk Shroud (subtle Diablo II reference? I hope so!). This is your standard damage aura fight, similar to Blood Queen Lana'thel or the Twin Val'kyr. You can assist with healing any targets that are low, but let your AoE healers handle the bulk of the raid healing here. Halion doesn't stop casting debuffs in this phase, though they're now called Soul Consumptions instead of Fiery Combusions. They work in exactly the same way as the fiery originals, except that they draw players in instead of knocking them back. Think of the Gravity Bombs that XT-002 uses, including the nasty patch of void zone that they leave behind.
The last change is that Halion has replaced his Meteor Strike ability with Twilight Cutters. These are lasers that will basically slice the room in half (or into quarters on heroic) and then begin to spin. If you're hit with one of these lasers, you'll pretty much instantly die. They spin clockwise, and so you have to run clockwise fast enough to avoid them. If you're familiar with the Mimiron encounter, it's similar to the Laser Barrage ability he uses in phase 2, except that there are additional beams.
The twilight realm is all about mobility, which means we're pretty useless here. Use Holy Shock every time you can, use any Infusion of Light procs to toss out a Flash of Light, and basically just do what you can to keep the tank up while spot-healing the raid. You're just riding this out until phase 3. Feel free to pop Aura Mastery with Shadow Resistance Aura up or use your Divine Shield to Divine Sacrifice macro during this phase to help out the other healers, since you won't need them in phase 3.
Nothing actually changes in phase 3, your raid will just be splitting up into groups to assault him from the physical and twilight realms simultaneously. Plead with your raid leader to let you heal the physical side, since that's where you'll do the most good. You'll take a portal from the twilight realm back up to the physical realm, where you'll fight Halion exactly as you did in phase 1. It's actually quite a bit easier than phase 1, since only half the raid will be up top and that means it's easier to spread out and avoid damage.
Beacon and Sacred Shield the tank and just continue your usual Holy Light spam strategy while dispelling anyone with the Fiery Combustion debuff and dodging fire. Your druids and priests will have to handle dodging the twilight cutters and healing the pulsing shadow aura on their own, since that's what they're good at. Your tank might take some additional damage if your DPS in the twilight realm is too powerful, but that's okay, because you're just bombing the tank with Holy Light, right? Unless things are seriously imbalanced, Holy Light will take care of all healing requirements and the fight will be over in no time.
Halion's not a hard fight, though it does present a few new interesting mechanics to enjoy. Phase 1 and 3 are going to be pretty easy for us, but that's just the nature of only having one button to push. Phase 2 is where everyone falls apart, and I guarantee that you'll die to the lasers the first time you're in the twilight realm. We're just trying to keep things together long enough for phase 3 to start so we can go back to the physical realm, where we can actually get some healing done without running around all the time. Once you learn to dodge the Twilight Cutters, you'll have your role on this fight on lock. Here's hoping that your guildmates pick it up as fast as you do!
The Light and How to Swing It (Holy Edition) is dedicated to helping holy paladins become the powerful healers that we're destined to be. If you're new to the paladin's healing ways, you can learn the ropes with our Holy 101 article. We also have information on how to keep a tank alive, how to heal a raid when necessary and how to beat the GCD. Tanking is a job, DPS is a craft -- but healing is truly an art.