Before Pull
Pop a Shadow protection potion. Get an healthstone from warlock.
Make a healing rotation for the main tank with other healers. Create a macro to yell “xxx healed >>> xxx next”
Equip your smite gear if you have
The fight
It’s not an usual fight.
Basicly, each time you throw a heal, you’ll get a debuff preventing you to use another healing spell for the next minute or so. This is why you’ll only heal the tank and you’ll only do so when it’s your turn in the healing rotation (wait for a 3-4k hp deficit before throwing a R5 GH). When you don’t heal, just smite the boss. R4 smite is the most mana per damage efficient rank if you’re getting low on mana.
Additionally, there will a debuff on every raid member. This is a 10s debuff, after which it damages everyone.
What you can do tho, is using shield. It will not trigger the “can’t heal debuff”. But if you already have the debuff you can’t use it tho.
So if you are lucky in the rotation, you can shield yourself before shadow damage happens. This will allow you to pop mana pot instead of shadow pot during the fight and pewpew the boss a bite more.
Also watch raid, and shield dps if they seem low on hp.