There are four relevant mechanics for you during this fight, the first one is 378029 in which 186124 will dash towards each player and apply a heavy bleed on them
that lasts either 15 seconds or untill the person is healed above 90% HP. Preservation has a special trick to deal with this mechanic in the form of stasis and caut:
As you approach the boss, press stasis and then use caut on two of your dps. Because there is nothing to dispell caut will not go on CD but will still be saved
in your stasis. A couple of seconds after the boss is pulled you caut the last remaining dps and now your stasis is full. When 186124 does 378029
you can then release your stasis which will send a caut to each one of your dps instantly clearing them of the bleed, and you still have caut off cd to clear yourself
378029 is cast every minute, so you won't have stasis for each of them but can do this trick for every other, and caut is up every minute so you can clear
atleast one person every set. Without stasis your best bet to top the group is either lb, sb or both combined. You can also use tts every other
378029 so alternating between it and stasis can be a good plan
The second mechanic is the combo of 381694 and 381470. The 381470 will polymorph you, making you unable to do anything while 186124
uses 381694 on the tank, disorienting him. Your dps will break the 381470 and you have to dispell 381694 from the tank as soon as you are free
in order for him to get into position to soak the 381416 from 186122
Then, 378229 will focus down one player and deal constant damage to them which you need to heal, td and tg are good tools to help with that and this mechanic
shouldn't be a big problem, if you are the target you can also rb to mitigate it. The final thing to consider is 186125 constantly casting 378155 on random
players dealing a notable amount of damage, as usual with this kind of mechanic you need to keep an eye out for casts overlapping other mechanics or hitting the same target back to back