Algalon the Observer

Encounter Details

Remember, Algalon the Observer is Hard Mode only, meaning the encounter does not have multiple difficulties!

Algalon the Observer
Basics
HP: 34.9m (Heroic) / 8.37m (Normal)
Time Limit: 1 hour
Enrage: Unknown
Abilities
Ascend to the Heavens
Inflicts 655500 to 724500 Arcane damage to enemies.
Big Bang
Inflicts 107250 to 112750 Physical damage to nearby enemies. Triggers Remove Player from Phase.
Note: When Algalon casts this, you must step through the Black Holes spawned to avoid it. This will place you in another phase, and when Big Bang's cast time is up, you will be brought back to the fight.
Black Hole
Inflicts 1532 to 1968 Arcane damage every 1 sec.
Note: Stepping through the Black Hole will protect you from Big Bang. These spawn when you kill Collapsing Stars.
Cosmic Smash
Calls an abyssal boulder from the sky, dealing 53625 to 56375 Fire damage.
Note: This is cast every 25 seconds at a random target player's location (3 random players on heroic). The player(s) must move out of a spinning red circle before the boulder hits.
Phase Punch
Massive blow that inflicts 8788 to 10212 damage and slowly fades the target to another plane of existence.
Note: When Algalon uses this on your tank, it places them in another phase. You'll need multiple tanks to mitigate the effects of this.
Quantum Strike
Strikes at an enemy, inflicting 34125 to 35875 Physical damage.
Note: This is an ability Algalon uses throughout the encounter. You can see it in the video below as a purplish arc in front of him when used.
Adds
During the encounter, Algalon will spawn multiple types of adds. There are also adds spawned in the alternate phase.
Collapsing Star
These adds must be killed in order for you to avoid Big Bang. Killing them triggers Black Hole Explosion, which will open a Black Hole at the location of their death.
Living Constellation
These do an Arcane Barrage attack on targets. Killing them isn't entirely necessary, unless you're concerned with minimizing damage as much as possible.
Dark Matter
Dark Matter are spawned inside of the alternate phase the tanks and players who use the Black Hole are sent to. They hit for about 2-3k damage.
Unleashed Matter
Much like the Dark Matter above, these are spawned by Algalon the Observer when he reaches 20%.

Video

Now that you've read up on the encounter, take a moment and watch this video to see things in action.

Apathy versus Algalon the Observer