Normal: Interrupt or dispel Wither. Kill the Seedling Pods that spawn around Ammunae. If a Bloodpetal Blossom spawns, tank should grab it. Move out of any spore clouds that are created.
Heroic: Killing Seedling Pods is more important, as they heal Ammunae 1% every 3 seconds they exist.
[Consume Life Energy]—Drain life and power, granting the caster Life Energy. Grants 10 Life Energy
[Rampant Growth]—Ammunae releases all of life energy, bestowing life to all nearby Seedling Pods, and dealing 25000 Nature damage to all nearby enemies.
[Wither]—Reduces the attack and casting speeds of an enemy target by 60% and slows its movement by 60%. Lasts 10 sec.
[Thorn Slash]—Inflicts 150% of weapon damage to an enemy and causes it to bleed for 3200 damage every 2 sec for 15 sec.
[Energize]—Seedling pods provide energy to Ammunae. Stacking buff
[Energizing Growth]—Energizes Ammunae.
[Spore Cloud]—Inflicts Nature damage every 1.50 sec. to all organic life.
[Noxious Spores]—Deals 10574 Nature damage to all enemies within 60 yards, and cause plant life to rot.
Work in progress.
Currently, it's easiest to brute force this boss.
It's probably intended for you to use the Spore's death AOE to kill the Bloodpetal Blossom.
It is also probably intended that you kill the Seedling Pods.
DPS will need to focus on the boss and let the tank kill the pods. This works best with a Death Knight or Paladin tank. You can also use a melee dps to quick kill the pods since they only have 20k health.
Kill pods the moment they bloom, it's easier than killing the flowers
Kill any pods that form into flowers
Kill the boss
The tank needs to keep an eye out for the Spore and taunt it to him where it's death will both harm the boss and create a dirty brown pool on the floor
Position the boss into the brown pool while avoiding it yourself
If the tank kills the pods quickly you will prevent the boss getting heals, dps can quickly take this boss down with only a tank and maybe one dps on the pods.
Ammunae's name is most likely based on Amun, the Egyptian god of creation and the wind, whereas his appearance is likely based on Khnum, a nile god with the head of a ram, considered to be a god of creation due to his moulding of people on a potters wheel using mud from the Nile, explaining Ammunae being the Construct of Life.