Under construction, will amend as info comes in.

Strategy assumes familiarity with current Guild strategy on HM.

S&V

Spoiler:

From Shin:

Thrasher strategy:

1/ Mechanic:
_Knock up: (Understand this can help you avoid getting cleave by moving to the front of Thrasher at the right time when he's under 50% hp).
+Every time snipers group spawn ,there will be a Frenzy buff on Thrasher. Frenzy lasts about 10 seconds ,1-2 seconds after Frenzy ends, Thrasher will do his knock up skill (she doesn't do her knock up skill right away after Frenzy ends).
+When Thrasher is under 50% hp ,this is when we may need healer and dps to get in front of Thrasher to get knocked up together with the tank in order to take care of the front snipers group. There's a small chance that Thrasher will use his cleave , so the healer and dps need to watch out for the Frenzy's buff duration , only move in front when there's about 2s left on Frenzy . The idea is the less time you stand in front of Thrasher , the less chance you get cleaved.

Frenzy buff

2/The fight:
_ Tank swap everytime snipers spawn , 1 healer and 2 dps will go up with the tank who got threat on Thrasher . 1 dps kill the snipers ,the other one takes care of Demolitionist (the dps on Demolitionist needs to call out the red reticle when there's 1-2s left on "Loading" , the call out is very important ,failure to call out any shot the demo fire can kill one person if they don't react fast enough).
+Once the tank got knocked up , use aoe taunt and 1 defensive cd . Riot Gas for Vanguard and Saber Reflect for Guardian work great here and will come off cd everytime the tank get knocked up. (Snipers deal a shit ton of damage , can't let them target healer/dps for more than 3-4s and going against them without any cd is suicide )
+Dps and Healers need to use Threat Drop everytime snipers spawn . Watch your hp and use defensive cd if needed .
*You can know if the snipers are targeting you or anyone else by watching the target mark on the character (it looks like Ambush or Aimed Shot of Gunslinger)

_After the snipers are dead(and demo too) , the group on top come down ,stack right behind Thrasher for Salvation if there's a sage in the group (the salvation should hit 7 people --> max effective) , everyone except the tank on Thrasher should be at nearly full hp before the next snipers spawn in case shit happen and 2-3 of them hit 1 person at once. Stop stacking when snipers spawn to make it easier to see and avoid red reticle.

_Rinse and repeat till Thrasher is under 50% (which he should be after 3-4 group of snipers spawn)

_Double Snipers phase: (Thrasher under 50% hp)
Option A: The group that has been going up (except the tank) will need to stay on top after the snipers group right before 50% are dead and  move to the front side to take care of the front snipers group (the side where Bo Zarran's stage is).  

Option B: The group that has been going up (except the tank) will need to get in front of Thrasher when his Frenzy buff has 2-3 seconds left and get knocked up together with the tank to take care of the front snipers group.

*There's a small chance that Thrasher will use cleave and kill someone when the front group move in front of Thrasher with option B.

+The group that has been on the ground will stand behind Thrasher and wait for the knock up and take care of the back snipers group.
*The knock up when Thrasher is under 50% hp has 360 degree range (very similar to Stormcaller and Firebrand in EC) ,so you can position yourself to get knocked up to the side where your snipers group spawn.

+Tank that has threat on Thrasher face the boss toward Bo Zarran's stage and take care of the front snipers group. The other tank take care of the back snipers group.
+Demolitionist: if he spawns near the front group then the dps that has been killing him can take care if it .  If he spawns near the back group, one dps in the back group will need to be assigned to kill him + call out red reticle.
+For tanks: who's side got snipers down first will take the boss

Map:

1: The entrance where we come in.
2: The side where Bo Zarran's stage is
3: The opposite gate
Star: Where Thrasher is at the start.
*Front snipers group will spawn randomly on either A or B . (Front group run to 2 and wait till snipers spawn if doing option A)
*Back snipers group will spawn randomly on either C or D.


_Recover after double snipers:
+This is the period when we got the 2 snipers group down and the next group is about to spawn,everyone's cd is most likely not available due to using it in order to survive the double snipers phase , 1 gunslinger will need to save their scrambling field and use it for the upcoming group . Everything will be less frenzy if we got past this group of snipers and if we don't hit enrage at 10-15% +.


p/s: If you think there are something wrong this strat and don't agree with it or there are better ways ,feel free to point it out .



Where to tank Styrak: A and B
Where Not to tank Styrak : C,D,E and F

Question: Why?
*What's hard about this fight is not the healing ,it's the tight enrage so the more dps the better.
1)Salvation will heal everyone (including the tanks) -->the max effective of salvation , if healers can heal less,they can put extra dps on the boss.
2)The less the group has to move,the more dps can be done.
3)Gunslinger will know where to put their flyby ahead of time . Also if there's a flyby in the ground and Styrak casts Chained Manifestation ,the flyby will also hit transformed Styrak at middle too when he appears. -->The more dps the better. The below picture happened 1 second after the first picture (the big Styrak appeared right next to where Styrak was tanked previously)


Question: What about Thundering Blast?
_Keep Styrak at one place and dps/healer will know where to stand (behind him) to avoid it , if the tanks keep moving Styrak ,it will only cause dps/healers more confusing.

Difficulty: I have to move during Lightning Manifestation,so position Styrak at A or B may be hard.
_During Lightning Manifestation: a combo of tank+dps will kill the add faster then a combo of healer+dps ,so if everyone does their job right,the tank won't be the last one to finish killing his add. So,when the tank finish killing the add, move to A or B and wait for Styrak comes out and taunt him. Don't bother attacking other adds unless you can attack them from 30m (Saber Throw,...) .

TL:DR: stacking is op with salvation.

Video for anyone who's interested:

Spoiler:

p/s: feel free to ask any questions or suggestions.