Cosmic Observatory Strike Mission Strategy Guide

This guide provides tips and strategies for the thirteenth strike mission and how to defeat Dagda in the Cosmic Observatory. If your group is struggling, the guidelines in the Introduction to Raiding will apply here as well. Check out the glossary page if you're not familiar with a term used in this guide and make sure to run an optimal build from our list of recommended builds for this encounter.

Introduction

Through the barrier, Dagda awaits. She is a relatively simple boss with only a few key mechanics, but the punishment for repeated failure is quite high.

Dagda will only ever move as part of mechanics, and many of her attacks only hit players in melee range. A group that is really struggling to survive could stack a short distance away from the boss and range her, but this is quite an extreme approach.

Note that while Dagda becomes untargetable during split phases, she never becomes invulnerable, which means that condis will continue to do damage and may be more optimal here as they allow new phases to start at lower health.

Unlike most raid and strike encounters, this fight does not have a boon rip at the start, nor will it refill class-specific resources such as Life Force.

Strategy

The fight starts as soon as someone attacks Dagda. Dagda will target the closest entity (including pets etc.) with her auto chain, so players taking a lot of damage can back away slightly to gain a respite.

Dagda's basic attack chain is Strike ⇒ Vengeful Strike ⇒ Starburst. The final attack of this chain fires a cosmic projectile that can be blocked, or reflected for a bit of damage.

Challenge Mode

Dagda starts with 10 stacks of Demonic Aura, each stack of which reduces the damage she takes by 10%. Throughout the fight, Purifying Light AoEs will spawn (see the Soul Feast mechanic in Phase 2) nearby, and using the Special Action Key on Dagda will remove five stacks. Once all her stacks are removed, she will gain an effect called Demonic Aura Timer that last for 20 seconds. After the buff expires, she will regain all 10 stacks.

Additionally, there is now a 10-minute Enrage Timer.

Finally, the encounter starts with Planet Crash (see Phase 3).

Phase 1

Shooting Stars

Every 1-3 auto chains, Dagda targets a random player with a large green arrow that will deal 90% of that player's max health as damage after seven seconds. The targeted player receives a target symbol above their head and an on-screen message: "Beware the Shooting Stars. Hide behind your allies!"

If at least five players stand between Dagda and the targeted player, then each of them will instead take 10% of their max health, while the target takes 20%. Otherwise, every player other than the target will take 50% of their max health as damage and receive a stack of Infirmity for 30 seconds, reducing incoming healing by 25% per stack.

The targeted player should take a few steps back (at least to max melee range) and remain stationary, while every other player should stand in front of them.

Challenge Mode only: If this mechanic is failed, the target will be killed instantly.

Spinning Nebula

Every so often, rather than , Dagda will spin in place, firing out multiple projectiles in all directions and pulsing heavy damage in the area around her. The projectiles can be blocked or reflected, though they deal no damage to Dagda when reflected.

If Dagda is below 90% health, she may teleport a short distance away to perform this attack, but she will teleport straight back to the center afterward so it may be worth just waiting for her to return.

Challenge Mode only: The projectiles apply Debilitated and can no longer be blocked or reflected.

Starting in Phase 2, a ring of large, immobile Soul Feast AoEs will appear some distance away from Dagda.

Demonic Blast

At 90% health, Dagda will become untargetable for a few seconds, then fire out a conal attack in eight directions after a three-second delay, dealing very heavy damage to everyone hit, in addition to applying three stacks of Residual Anxiety, one stack of Debilitated and summoning a Tormented.

This attack repeats at 75%, 50% and 25% health (coinciding with phases), but is often skipped if she is performing another attack when the threshold is passed.

The Tormented that spawn during this attack appear near the stack and will often be cleaved down before people even notice them. The other two effects are more serious: Debilitated lowers the player's damage by 25% for 60 seconds, and Residual Anxiety can turn players against their allies if they reach 10 stacks (see below for more details).

Demonic Fever

Below 90% health, seven players are targeted with a medium-sized AoE that will explode after five seconds, dealing 20% of the targeted player's max health as damage to anyone inside. Players hit by multiple AoEs will take a further 200% of their max health as damage, downing them.

Split Phase 1

At 75% health, Dagda becomes untargetable, repeats (maybe) and starts pushing players toward the edge of the arena while filling the middle with a large red AoE that ticks for 20% of a player's max health. The red AoE takes a long time to start dealing damage, and the split will frequently coincide with other mechanics so prioritize handling other mechanics correctly.

Groups with a lot of condi damage may wish to start moving towards the edge when Dagda hits 76%, to make mechanic overlaps easier to handle.

Two Tormented spawn near to each other at a random spot near the arena's edge. Kill them both to start the next phase.

Challenge Mode only: The Tormented that spawn in the split phases are now a mixture of Elites and Champions, and the Champions have the ability to summon additional Tormented.

Additionally, one player will be targeted by Soul Feast as the phase starts (see below).

Phase 2

Phase 2 is very similar to Phase 1, with the addition of one new mechanic:

Soul Feast

Approximately 30 seconds into the phase, a random player becomes the target of , and receives the on-screen message: "You are targeted by Soul Feast. Run!"

A targetable, but undamageable, red puddle spawns on the player and follows them around for 15 seconds, dealing a small amount of damage and applying a stack of Residual Anxiety and Infirmity to each player hit.

At the same time, two small white AoEs spawn nearby, and any player can run into them to receive a Special Action Key called Purifying Light. This ability is a single-use attack that will destroy the if it hits. Be aware that the attack can be body-blocked by Dadga, so aim carefully.

The puddle is difficult to see, and the targeted player only receives a text notification that they have been targeted. As the attack is also very dangerous, everyone should be alert for this mechanic.

Challenge Mode only: After being targeted, a series of five Soul Feast puddles appear beneath the player over five seconds. With so many of them, they are difficult to disable with Purifying Light, so the targeted player likely needs to kite them away from the group instead.

If the Soul Feast puddles are allowed to touch Dagda, she will gain a stack of Demonic Aura per tick.

The mechanic in this encounter applies stacks of Residual Anxiety, which last for three minutes. This debuff has no inherent effect, but if a player reaches 10 stacks they will switch sides and become hostile to the group. While hostile, players retain control of their movement but will be repeatedly Taunted onto other players. The hostility will end early if the player is downed or CC'd, and it appears that the effect can be condi-cleansed. Stunbreaking the Taunt will prevent the forced attacks, but the player will remain hostile and be Taunted again after a short duration.

s that have been hit by Purifying Light will remain visible until they expire, but no longer have any effect.

Charging Constellation (Challenge Mode only): Five random players are marked with a roman numeral above their heads. After a short delay, Dagda will fire an attack at each player in order. Each hit applies Extreme Vulnerability in an AoE, killing the player instantly if they are hit more than once. The targeted players should spread out away from the stack until they have been hit.

Meteor Crash (Challenge Mode only): Two random players are targeted with a green AoE. Three players need to be in each or the group will take extreme damage. Although the AoEs have visual indicators suggesting that too many people can be in the AoE, there seems to be no downside to stacking them together with everyone inside.

Unlike Phase 1, Dadga's attack patterns are fairly reliable in this phase:

Auto Chain x2 ⇒ ⇒ Auto Chain x2 ⇒ Spinning Nebula ⇒ Soul Feast ⇒ Auto Chain ⇒ ⇒ Repeat

In Challenge Mode, the pattern is:

Charging Constellation ⇒ Auto Chain x2 ⇒ ⇒ Meteor Crash ⇒ Auto Chain x2 ⇒ Spinning Nebula ⇒ Soul Feast ⇒ Auto Chain ⇒ ⇒ Repeat

Split Phase 2

At 50% health, Dagda becomes untargetable again and repeats the split phase as before, only this time four Tormented spawn. As they spawn across a large area, it may be worthwhile sending half the group to one side of the arena, and the other half to the opposite side.

Phase 3

Phase 3 begins much the same as Phase 2, though spawns at around 25 seconds.

Rain of Comets

Approximately 30 seconds into the phase, Dagda raises an arm above her head and summons a Rain of Comets to pelt half of the arena for five seconds, indicated by a large red AoE. For the entire duration, this area ticks for 25% of a player's max health.

Challenge Mode only: The same pattern of Soul Feast AoEs that appears during Spinning Nebula will appear during this attack too.

Planet Crash

Approximately 45 seconds into the phase, Dagda raises her sword high and summons a massive orb of energy. The group has 10 seconds to break her defiance bar (strength:3600) or she will slam the orb into the ground, dealing 90% of each player's max health across the entire arena.

Breaking the bar will instead cause the orb to shatter, raining down energy around Dagda, but only dealing minor damage. Dagda will be Exposed for five seconds after being broken.

Challenge Mode only: Failing to break Dagda is in instant wipe, and each time she is broken, she gains a stack of Planetary Weight. This effect should reduce the effect of incoming CC, but it currently appears to do nothing.

In this phase, her attack pattern is:

Auto Chain x2 ⇒ ⇒ Auto Chain ⇒ Spinning Nebula ⇒ Soul Feast ⇒ Auto Chain x2 ⇒ Rain of Comets ⇒ Auto Chain x2 ⇒ Planet Crash ⇒ (only if not stunned) ⇒ Auto Chain x3 ⇒ Spinning Nebula ⇒ Rain of Comets ⇒ ⇒ Repeat

In Challenge Mode, the pattern is:

Auto Chain x2 ⇒ ⇒ Meteor Crash ⇒ Auto Chain x3 ⇒ Spinning Nebula ⇒ Soul Feast ⇒ Auto Chain x2 ⇒ Rain of Comets ⇒ Auto Chain x2 ⇒ Planet Crash ⇒ Charging Constellation ⇒ Repeat

Split Phase 3

At 25% health, Dagda becomes untargetable again and repeats the split phase as before, only this time six Tormented spawn. As they spawn across a large area, it may be worthwhile sending half the group to one side of the arena, and the other half to the opposite side.

Phase 4

The final phase is identical to Phase 3.