Well, there is not much to do in here from off tank perspective. Thats why ill be generally explaining whole fight mechanics Neverthless, the main goal of off-tank is to protect main tank with guard and adds positioning. There are three phases to fight: Gargolye breaking, Warrior Burn, Starfall. Notice group stack. Main tank in front, then Gargolye, then group. We are all stacked perfectly in line between two Gargolyes. Boss will be faced towards the group. People are slightly away from first gargolye to avoid cleave. When boss does shield throw (everyone blocks) it will break both first gargolye and last gargolye.
Move to next position. Notice special attack that turns people into stone. First wave of adds, taunt and keep in stack close to boss. Every few dozens of seconds boss will turn one person into statue. Its called Destructive Outbreak. In stone form you cant do anything and if you use synergy you explode with large AOE that 1-shots everybody. In initial phase you are meant to wait untill boss throws shield to set you free. DO NOT SYNERGISE. At 85% boss jumps away to break buff statue. Normally group wants to throttle DPS to first break Gargolyes. Jump attack also breaks statues. You can make use of it like here, stacking on Gargolye. And very lucky shield throw. Look at person stoned on right, nobody is around so they break free (synergy). Notice large explosion. With time one of Gargolyes will come alive. Two ways to handle this. Either off tank holds it and people nuke it while main tank kites boss or simply main tank stacks both together. Be wary tho of smash attack that will melt anybody in its radius. If there is no Negate, everybody have to stay clear out of it. The thing with last two statues is that you can either follow original strategy (stack between for throw).
Or have boss stay at the edge of circle while rest of group stacks on first Gargolye for shield throw and then moves to other one. This lets DPS start focusing on burning boss to avoid soft enrage (all statues come alive). Warrior is hardest hitting boss. His burst is insane so it will happen a lot that Tank dies. Off tank needs stay sharp to take boss over. That RNG stone form. Look what group does. With last statue (almost) gone, this turns into “normal” vHRC. Boss stacked at the edge of blue circle (so group have DPS buff but boss does not) and group stacks on stoned people so shield throw sets them free 100% of time.
When stoned players are spread apart, you just gotta wait. Finally. Btw. stone form will explode on its own after two minutes… Off tank back in action, taunt flameshapers and kite them on top of boss so they can be cleaved. While doing so please try to stay in line with boss/group so you dont coerce shield throw. Damage control. Both tanks dead, what to do? Whoever gets boss aggro should run FAST AND FAR untill tanks get res. Beginning of starfall phase. We are almost done. Each boss rotation he will hold his sword up and call starfall. It damages each player with small AOE attack – group must be spread out, everyone blocking. Tanks helping with vigors. Here it comes. Notice AOE on your feet. Stacking on someone will kill you both. Remember that you still can get stoned in this phase. Tho this time its handled in different way. When someone gets stoned they announce it and everybody must get away from them to give them space.
Pro tip. When boss turns someone into stone, there is a few second cooldown before he will do it again. When you see or hear someone getting stoned, you have a brief moment to freely use synergies without risk of wiping group. Starfall repeats untill boss is dead. From here remember to not stack. Dont wipe group. And stay sharp. There is also this wide frontal wave attack. It sets people free of stone but also knocks back everyone even if they block. And this is what kind of damage is done when someone uses Outbreak in middle of stack. Damage seems low but it will always scale to 1-shot you no matter how much HP you have..
As found on Youtube