There is an issue with a mechanic in Dreadsail Reef on the first boss: Lylanar and Turlassil after activating the challenge banner.

The mechanic in question is the firebrand and frostbrand mechanic. When both bosses are down, they will choose 2 people to have brands (1 frostbrand and 1 firebrand) which will explode after a short duration. To avoid deaths to this mechanic's explosion the players who are picked are supposed to stack on a player with the opposite brand color to mitigate the damage. On hard mode this mechanic changes to pick 4 people (2 frostbrands and 2 firebrands) and in addition to this, on brand explosion there is an additional straight line, aimable AOE that shoots out of each players' brand explosion. Crisp Flurry is the white straight-line AOE that shoots out of frostbrand (as pictured below) and Pyretic Wake is the straight-line AOE that shoots our of the firebrand, but in a red color.



Before Firesong patch, you stacked on someone with the opposite brand, aimed your Crisp Flurry/Pyretic Wake AOE to not shoot towards your team members, and blocked the explosion of the brand. Nobody died if done correctly. After Firesong patch, no matter how early and correctly people play out this mechanic, people are dying at random, no sense of logic or cadence to the deaths. Very rarely, all 4 players will live. Much more commonly at least 1-2 players will die and sometimes all 4 players die. Looking at death recaps of these players we realize that the Crisp Flurry and Pyretic Wake from the 2 players are killing either their stacking partner or even themself.

Either before the patch, the damage done by Crisp Flurry and Pyretic Wake to players marked with brand was negligible, or the AOEs just never hit people within the stack. We have tried stacking in a different manner, in which both players with brands intentionally not have their character model stacked directly on one another so their Crisp Flurry or Pyretic Wake wouldn't hit their stack partner, but just enough so the players don't die to the brand explosion not being stacked. In this case, players died to their own Crisp Flurry or Pyretic Wake, not from their stacking partner, nor from the other 2 players with brands.

This bug is making simple progression of the fight exponentially harder and progression of the trial's trifecta near impossible, as it is now to be expected that every brand someone dies. I wish I had more information to give, but since logging the fights are currently bugged I cannot provide anything more.