Keep Construct

Enrage: 10 minutes. When Enraged, Keep Construct will deal 200% damage.
Tank: Toughness

Keep Construct heavily favors builds that deal high power damage due to its low Toughness compared to other raid bosses and its short burst phases. Additionally, adds will spawn that must be quickly cleaved, further biasing the encounter towards burstier classes. Power Bladesworns, Soulbeasts, and Catalysts are all common on this boss due to fitting exactly this profile, but any power DPS build is a viable pick.

While Keep Construct requires a Toughness tank, tanking is straightforward and can be done comfortably by most support builds.

Enabling the mote outside the arena activates the Down, Down, Downed achievement, which is Keep Construct’s “Challenge Mode” (with the associated extra weekly rewards).

The only difference with the achievement enabled is that the playable space is permanently reduced during the encounter. This does not change the approach to the fight in any way, so the following all still applies.

The encounter begins when players approach the center of the arena. The tank should remain against the edge and allow Keep Construct to approach them.

Keep Construct starts the fight with two stacks of Xera's Embrace, which need to be removed in order to progress the fight to the Exposed Core Phase, which makes the boss vulnerable to massive damage.

When a Projection dies near Keep Construct, it will remove one stack of Xera's Embrace. Once the boss’s two stacks are removed, Keep Construct will gain a breakbar. Reaching and breaking this bar quickly is ideal in most scenarios, as breaking it activates the Exposed Core Phase.

If two Projections get close to one another, they will stop all other movement to merge, becoming a bright red Insidious Projection. The Insidious Projection does more damage and has a frontal smash attack that strips boons from the squad. Many groups will call for a reset if a merge occurs, so this situation should be avoided at all cost.

Generally, the close fixate should stand on the opposite side of Keep Construct from their Projection to make their Projection walk into Keep Construct and into the squad’s cleave. The far fixate should keep an eye on the first Projection’s health, pulling their Projection slightly off group if the Projections are at risk of merging. Otherwise, they can walk through Keep Construct to pull their fixate in as well.

Whenever the boss is free to move, it can choose between one of the following three mechanics at random. All three mechanics will be cancelled if the boss’s breakbar is active and is broken in time.

Fixates should stay on Keep Construct to ensure that the Projections will not die far from Keep Construct. Additionally, if a Projection is pulled far from Keep Construct, squads will often struggle to re-target and kill it, making an Insidious Projection merge much more likely.

Hail of Fury

In addition to the two random mechanics above, when under 33% HP Keep Construct will occasionally float into the sky, dropping rocks onto the arena. The squad should treat this mechanic as though Keep Construct hasn’t moved—killing Projections where Keep Construct floated up from will still strip stacks of Xera's Embrace.

Exposed Core Phase

Once Keep Construct’s bar has been broken, Keep Construct will retreat and three green circles will spawn on the arena. Each circle must have at least two players in it by detonation or the squad will wipe.

After detonation, a pink Construct Core will appear in the middle of the arena. The arena will also gain a pink border and five Ley Rifts along the edge.

The Core can be pushed by any attack, but dedicated crowd control such as pushes, pulls, and launches will work as well. One player should be assigned to handle this mechanic, but other players can help if requested. Often, a Druid will be designated as the pusher; this player should remember to disable their pet’s attacks so they don’t erratically push the orb.

The squad should aim to push through enough rifts to phase Keep Construct during the burn phase. Keep Construct phases at 66% and 33% HP remaining, so if he is near that health when the Core is exposed, only one rift should be necessary. If his health is far from these thresholds, more rifts should be captured: five rifts is always the safest bet, but groups with good damage can usually manage with three (or even less).

If at least one rift was captured when the Core is retrieved, when he respawns Keep Construct will be Stunned for twenty seconds and will gain stacks of Compromised: this is known as the burn phase. If players do not manage to push the boss to 66% or 33% during the burn phase or do not capture any Rifts, Keep Construct will regain two stacks of Xera's Embrace and the fight will continue as normal.

Note: If Keep Construct is very close to one of the HP thresholds when leaving the burn phase, it’s often better to ignore the breakbar if it appears and instead focus on getting his health over the line, since breaking the bar forces the squad to go through the entire Exposed Core phase again.

Magic Blast

At 66% and 33% HP remaining, Keep Construct will become invulnerable and will start channeling Magic Blast, a massive explosion that affects the entire squad. Players will gain red or white markers over their head, and red and white balls will move towards Keep Construct. Everyone should block balls matching their marker from reaching Keep Construct.

Each ball that reaches Keep Construct will give him a stack of Magic Blast Intensity, which increases Magic Blast’s damage. At 15 stacks and above, Magic Blast becomes extremely powerful, and at over 20 stacks, the squad is liable to wiping without Protection.

Players will take a small amount of damage when capturing each orb. One common approach to counter this has a Druid drop a Water Spirit on Keep Construct, so players can auto attack the boss to regenerate health.

When the boss starts moving the group should restack to heal up from the blast and prepare for Phantasmal Blades.

Condition cleanses such as Glyph of the Stars are valuable during this section to help players who accidentally enter the pool’s hitbox.

At the end of this attack, two statues will light up to spawn Projections. The entire squad should run to one of them (usually the one on the eastern side), as Keep Construct will target a random player to leap on. The squad can Dodge, Aegis, or Stability this attack to avoid getting knocked down, and afterwards will be positioned perfectly to cleave down one of the newly spawned Projections. At this point, the fight proceeds exactly as it did at the start, with the exception of the Hail of Fury attack.