This is the second fight of Nighthold. It's a single phase encounter with a unique twist: the flow of time SHIFTS as the encounter progresses, which causes the timers on the boss' abilities to change, along with the attack and casting speeds and cooldown reduction of the raid group.
So basically it's a single-target fight with a single phase that varies in flow based on the current Passage of Time. The boss will occasionally spawn adds that must be killed in order to interrupt lethal abilities.
Abilities
Passage of Time: This shifts periodically. There are THREE states: normal, slow, and fast. All the boss' abilities, debuffs, and cast speeds are affected by this. For example, debuffs applied during fast time require more agile reaction times.
The time flow ALSO affects the raid: the players' cast and attack speeds will fluctuate based on the flow of time, as will cooldown recharge rates. Movement speed is also affected.
Burst of Time: These bursts travel through the air before manifesting as 6-yard circles on the floor. Don't get hit by these.
Chronometric Particles: Applied to current target (a tank). If the tank reaches 10 stacks of the debuff it will trigger a Chronometric Overload. This INSTANTLY KILLS the tank and deals very high raid-wide Arcane damage.
Time Bombs: Placed randomly on two random players at a time. They're inert until they expire, when they inflict heavy raid-wide Arcane damage. The damage is reduced based on distance from the debuffed players.
Time Release: Healing Absorb applied to random members of the raid group. When it expires, deals damage based on the amount of the absorb remaining.
Waning Time Particles: Adds that spawn occasionally. Can be tanked. They cast Chronomate on their primary target, and will attempt to continually cast Warp Nightwell which does raid-wide Arcane damage and increases the damage of successive casts. This is interruptible until the the particle reaches 30% health, at which point it becomes uninterruptible. When it is killed it drops a Temporal Rift, which the tanks can interact with.
Power Overwhelming: Channel cast every 65 seconds. Pulses heavy raid-wide Arcane damage that increases over time, can only be interrupted by a Temporal Smash (obtained from the Temporal Rifts dropped by the Waning Time Particles).
Temporal Orbs: These do damage to players who come in contact with them. They occasionally flow from the Nightwell. Deal moderate Arcane damage and vary in travel speed based on the current Passage of Time.
STRATEGY
Positioning: Group loosely to the left of the boss when it is engaged. The first Waning Time Particle will spawn on the left side, and they'll alternate sides after that. The Time Particle always spawns a fixed distance from the boss, so the tanks needn't bother moving the boss. Thanks should swap at every 7-9 stacks of Chronometric Particles.
DPS: Prioritize killing the Waning Time Particle above all else, to interrupt Power Overwhelming. Establish an interrupt rotation to make sure no Warp Nightwell casts get through. When the Waning Time Particle is killed, the tank should IMMEDIATELY interact with the Temporal Rift to obtain a Temporal Charge. This allows the tank to use Temporal Smash to interrupt the boss' channel of Power Overwhelming.
Time Bomb: Anyone afflicted with the Time Bomb should RUN OUT of the group. Pay special attention to debuffs when Passage of Time changes as it will affect the remaining time of the debuff.
Healers: Pay special attention to the Time Release Debuff, as it can wipe the raid if left unattended. When the time state is in the fast mode, healers will have much less time to react.
Burst of Time and Temporal Orbs: Avoid Burst of Time casts and Temporal Orbs. They won't kill a player right away, but they can add up to a lot of raid damage if many players get hit by them. Their speed is affected by flow of time, so take care when it's in fast mode.
So basically it's a single-target fight with a single phase that varies in flow based on the current Passage of Time. The boss will occasionally spawn adds that must be killed in order to interrupt lethal abilities.
Abilities
Passage of Time: This shifts periodically. There are THREE states: normal, slow, and fast. All the boss' abilities, debuffs, and cast speeds are affected by this. For example, debuffs applied during fast time require more agile reaction times.
The time flow ALSO affects the raid: the players' cast and attack speeds will fluctuate based on the flow of time, as will cooldown recharge rates. Movement speed is also affected.
Burst of Time: These bursts travel through the air before manifesting as 6-yard circles on the floor. Don't get hit by these.
Chronometric Particles: Applied to current target (a tank). If the tank reaches 10 stacks of the debuff it will trigger a Chronometric Overload. This INSTANTLY KILLS the tank and deals very high raid-wide Arcane damage.
Time Bombs: Placed randomly on two random players at a time. They're inert until they expire, when they inflict heavy raid-wide Arcane damage. The damage is reduced based on distance from the debuffed players.
Time Release: Healing Absorb applied to random members of the raid group. When it expires, deals damage based on the amount of the absorb remaining.
Waning Time Particles: Adds that spawn occasionally. Can be tanked. They cast Chronomate on their primary target, and will attempt to continually cast Warp Nightwell which does raid-wide Arcane damage and increases the damage of successive casts. This is interruptible until the the particle reaches 30% health, at which point it becomes uninterruptible. When it is killed it drops a Temporal Rift, which the tanks can interact with.
Power Overwhelming: Channel cast every 65 seconds. Pulses heavy raid-wide Arcane damage that increases over time, can only be interrupted by a Temporal Smash (obtained from the Temporal Rifts dropped by the Waning Time Particles).
Temporal Orbs: These do damage to players who come in contact with them. They occasionally flow from the Nightwell. Deal moderate Arcane damage and vary in travel speed based on the current Passage of Time.
STRATEGY
Positioning: Group loosely to the left of the boss when it is engaged. The first Waning Time Particle will spawn on the left side, and they'll alternate sides after that. The Time Particle always spawns a fixed distance from the boss, so the tanks needn't bother moving the boss. Thanks should swap at every 7-9 stacks of Chronometric Particles.
DPS: Prioritize killing the Waning Time Particle above all else, to interrupt Power Overwhelming. Establish an interrupt rotation to make sure no Warp Nightwell casts get through. When the Waning Time Particle is killed, the tank should IMMEDIATELY interact with the Temporal Rift to obtain a Temporal Charge. This allows the tank to use Temporal Smash to interrupt the boss' channel of Power Overwhelming.
Time Bomb: Anyone afflicted with the Time Bomb should RUN OUT of the group. Pay special attention to debuffs when Passage of Time changes as it will affect the remaining time of the debuff.
Healers: Pay special attention to the Time Release Debuff, as it can wipe the raid if left unattended. When the time state is in the fast mode, healers will have much less time to react.
Burst of Time and Temporal Orbs: Avoid Burst of Time casts and Temporal Orbs. They won't kill a player right away, but they can add up to a lot of raid damage if many players get hit by them. Their speed is affected by flow of time, so take care when it's in fast mode.