Aetherblade Hideout (CM)
Enrage: 10 minutes, when enraged everyone dies
Required: Crowd Control
Recommended: Reflects, Vigor
The Challenge Mode of Aetherblade Hideout strike introduces mechanics that require all players to make decisions on the fly. Misjudging can entirely wipe the squad, putting individual responsibility on every player.
While the mechanics are very punishing, they are quick to learn as only one mechanic truly differs from the normal mode of this strike mission. It is very important that you are familiar with the regular version of this fight before trying CM: knowing the normal mode will drastically reduce overall chaos while learning challenge mode.
In the Challenge Mode each enemy has a higher health pool and a larger defiance bar. Additionally, the strike gains a 10-minute hard enrage timer – failing to finish the strike in 10 minutes will wipe the squad. In addition to these structural changes some attacks are changed or have additional effects.
Mai Trin
Mai Trin’s attacks and attack patterns are unchanged from the normal mode. However, her Cleave attack will apply a stacking 
Exposed
50% & 33%: Split
The first 50% split-phase will look exactly like the normal mode, with small phantoms spawning around the arena casting moderately threatening attacks. The group has to kill them quickly to continue damaging Mai Trin.
The 33% split-phase is drastically changed from the normal mode.
During this phase, all phantoms will spawn in their usual places: the phantom with high health spawns in the NE corner of the map, the phantom with a large defiance bar spawns in the SW corner of the map, and a few additional small phantoms spawn around the arena.
The tethered split mechanic has much larger AoEs in the challenge mode. Additionally, anyone standing in someone else’s AoE at detonation will take extreme damage and a stack of Exposed
The green stack mechanic has been game-changingly modified. Instead of four players stacking negating the damage, only three players need to be inside the circle.
This is the first iteration of a stack mechanic in the game that punishes overstacking. If three players, the correct number of players, is stacked in the circle, two orbs will circle around the green AoE.
Anyone standing in a green circle at detonation will get a 
Photon Saturation debuff that lasts for 10 minutes. If players with this debuff enter the next green mechanic, they will instantly die.
Handling this mechanic can be approached in multiple ways. The most common is to just react to your squadmates by watching who is entering or leaving the greens. Alternatively, you can assign groups of people to handle this mechanic together.
One new-player-friendly strategy is to assign three groups of “buddies”. These groups will stack on three separate sides of the North-Eastern phantom. This reduces confusion from ambiguous positioning, making it easy to tell who is entering or exiting the circle. To keep the squad within the boon range, have three DPS players from party 1 stack on one side of the phantom, three DPS players from party 2 on the other side of the phantom, and the remaining four supports stack just in front of the phantom. A player without Photon Saturation will be targeted by the green AoE, so if each group handles the green together they will not need to shuffle to ensure the mechanic is handled.
Note: As the North-Eastern phantom can cast more than one green per split, it is crucial to kill this phantom first and deny two greens during one split phase. If that happens, your squad is lacking the damage required to defeat the encounter and you should /gg and correct your group setup.
Echo of Scarlet Briar
Scarlet has the same attack pattern as in normal mode, but her damage, health, and defiance bar are larger, making the fight longer and harder.
While her attack pattern does not change, her Slam attacks will apply the same Exposed
It’s crucial that you jump, block, dodge, or otherwise evade the wave as too many stacks of this debuff makes it almost impossible to outheal the boss’ other attacks.
Additionally, the center field of the Slam attack has a different AoE pattern. Standing in this strike zone instantly down you.
Due to the higher overall pressure in the fight and the additional ExposedExposed
Corrosive Poison Cloud
"Aftershock!"
Protective Solace
Chapter 3:Valiant Bulwark
Zealot's Defense
80% & 40%: Split
Both Scarlet split phases are the same as Mai Trin’s 33% phase. However, constant Slam and Cone attacks can make it very hard to handle the stacking mechanics of splitting orange AoEs and stacking in the green ones. Avoiding getting Exposed
Vigor
When you return to Scarlet after the 80% split-phase, the blue lightning attack will start. In the CM it will target two players instead of one and it will spawn much more frequently. Drop both lightning areas on the edge of the arena and stack them to limit the deadly areas.
Do not drop these in the North-East area where the green phantom will spawn, as this may slow killing the phantom, leading to multiple green circles spawns within one phase.
Dropping blue lightning attacks anywhere between South and West is the best practice.
60% & 20%: Deathray
During this phase, instead of a phantasm casting a deathray, two players be the target of a cross-version of this mechanic. Both of those players will get a special action key which will “stick” their lasers to a nearby “ferrous object”.
These “ferrous objects” are three bombs that spawn in the arena. At first, all of them can be damaged, but once one is destroyed, the two remaining ones will become invulnerable. When the deathrays detonate, the remaining bombs will also explode.
In this phase, destroy one of the bombs to create a safe zone, and place the deathray crosses on the remaining two (with a special action key while near the bomb).
Bearers of the mechanic have to make sure to place their deathrays such that they don’t cross over the safe spot. The spot of the destroyed bomb will be the only safe spot during the detonation.
While this mechanic might look chaotic and confusing, it becomes very easy once you experience it. To make this mechanic easier, the commander can mark one of the bomb locations as the designated safe spot as the bombs will always drop in the same places. Destroy the bomb at the safe spot, then align the deathrays correctly so they do not cover the marker.
