Let's start with the basic abilities. Primordial Strike is the main attack that he uses against his current target. Unless you're a tank, don't stand anywhere nearby as Primordius attacks in a 7 card cone. In addition, the current tank has a Malformed Blood which will become useful (we'll get to that).
Your raid is going to have a bit of a tough time trying to get their damage in. Mutated Abomination causes him to resist attacks from any non-mutated creatures (like us). Damage from non-fully mutated players is reduced by 50%.
You'll notice several pools surrounding Primordius. Living Fluid adds will spawn and make their way toward Primordius. This is where your tank switch kicks in. Your first tank who was on Primordius should peel off and make a beeline for the Living Fluid to help in bringing them down. The raid has to switch and start applying DPS as well and minimize the amount of Living Fluids getting through. If a Living Fluid manages to reach Primordius, he'll absorb it and increase his current mutation level (Mutate Primordius).
Evolution: That's what happens after Primordius gets mutated by a combination of an unknown amount of Living Fluids, Mutagenic Pools, and his natural evolutionary skills. Primordius' damage increases by 10% and he gains a new mutation. Thankfully, he has a cap of 3 mutations. You'll have to deal with these throughout the fight anyway.
Ventral Sacs: Sacs located around Primordius's frill periodically erupt, inflicted 30000 Nature damage to all players every second. Use healing and defensive cooldowns to help get through it.
Gas Bladder: A volatile mutation that allows Primordius to spray Caustic Gas, inflicting 1600000 nature damage split between all players within a 30 yard radius. You know the drill. Collapse and stay close when it's about to go off.
Acidic Spines: Primordius fires Acidic Spines at players every 3 seconds, inflicting 150000 Nature damage to all players within 5 yards of the target. Spread out around Primordius to minimize the effects.
Pathogen Glands: Allows Primordius to spray a Volatile Pathogen at a player, inflicting 60000 Nature damage every second for 10 seconds. Easy to heal through and the debuff doesn't last very long.
Metabolic Boost: A hyperactive metabolism allows Primordius to use abilities more often and increases attack speed by 50%. You'll need to respond with defensive cooldowns and the tanks may need to move up the rate at which they switch.
Erupting Pustules: Pustules erupt every 5 seconds, showering the area with corrosive blood that inflicts 277500 damage within 2.5 yards of the impact point. Stay mobile and pay attention to where these will land.
Now suppose you manage to kill a Living Fluid. What happens? The Living Fluid leaves behind a Mutagenic Pool
. It can Mutate Primordius
if he somehow steps on one. But it can also mutate a player.
Mutated player buffs and debuffs
Each of the following effects can stack up to 10 times. A player can only receive mutations if they step on a Mutagenic Pool. They end up taking 92500+ damage but will experience one of the effects below. If there are no mutations present, the mutation will be a harmful one. If a mutated player receives a dispel, all mutations are removed.
Helpful: Thick Bones - Increases all stats by 10%.
Harmful: Fragile Bones - Reduces all stats by 10%
Helpful: Clear Mind - Increases Mastery by 10%
Harmful: Clouded Mind - Reduces Mastery by 10%
Helpful: Improved Synapses - Improves Haste by 10%
Harmful: Dulled Synapses - Reduces Haste by 10%
Helpful: Keen Eyesight - Improves Critical Strike chance by 10%
Harmful: Impaired Eyesight - Reduces Critical Strike chance by 10%
After receiving 10 help mutations, the player becomes Fully Mutated
allowing them to deal full damage to Primordius. Any mutations picked up after 10 will be harmful mutations. Avoid all the pools when you hit your cap.
These Living Fluid adds will sometimes leave behind a Volatile Pool
which can mutate Primordius or
the raid. If Primordius steps on a Volatile pool, his mutation level reaches the maximum level and heals him for 10% of his maximum health. If a player steps on the pool, they suffer 370000+ damage and take on a harmful mutation. I don't think it's possible to control which set of mutations you get. Hello RNG gods, right?
This is a note for the healers. Whatever happens, go easy on the dispels. If a player screws up and manages to get too many negative ones somehow, it's on them to speak up out loud that they need to get their debuffs off of them. Otherwise, players on dispel duty should not
dispel unless someone on the team calls for it.
All in all, Primordius can be quite the variable encounter. It can be simple to handle or a real teeth grinder. It all depends on the combination of abilities Primordius ends up receiving. Use your Heroism later on when more players have a full set of helpful mutations so they can keep their DPS as high as possible. All of the various buffs look attractive but I liked getting 100% critical strike. I love seeing abnormally large DPS numbers (and my guess is you will too)!
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