This is why they must be aware of how the effect is stacking and change as necessary. from wilkinson's blog

Each of the principal levels in WoW WOTLK Classic is the  WOW WoTLK Classic Gold home of a Covenant that plays an essential role in the afterlife, however it is also the place of an extremely powerful global boss. One of the most exciting features that are new to WoW WOTLK Classic is the appearance of world bosses. Once a week one of these beasts will spawn, and players are required to fight them to have a chance to earn massive loot as well as additional Soulbind conduits, or Legendary Powers. The creatures will be rotated each week, so if players skip one, they'll be forced to wait three weeks before they get the chance to gain access to the world boss's associated loot. World bosses will be revealed as a world quest on the player's map and regardless of their Covenant affiliation players will be able to try their luck at beating one.

Four world-class bosses: Valinor as well as the Light of Eons in Bastion, Mortanis in Maldraxxus, Nurgash Muckformed in Revendreth And Oranomonos who is the Everbranching in Ardenweald. According to legend, Oranomonos was the eldest guardian of Tirna Scithe, but she has since wilted as did the great tree. She is a tree-like creature which Gorms consume. Although she's gone her body, she's still an powerful being and could be a threat to players. her Seeds of Sorrow can bludgeon even the heaviest tanks, and players will need to join forces with an elite healer to stop this. Here's how you can take on Oranomonos in WoW WOTLK Classic.

Similar to the majority of world bosses in WoW WOTLK Classic, players should take the time to complete this fight with a party. While it is possible in a group, defeating all of the bosses listed is a challenging job, and players would significantly benefit from working together. Oranomonos occurs in Tirna Scithe on the southeastern part on the island. She has six possible attacks with the majority of them dealing Nature damage. To stand up to these attacks players will have for them to have the most mobility they can and be prepared to heal quickly.

Whichever character a player is using to fight Oranomonos, they will want to stay away from her once she begins using Seeds of Sorrow and avoid the route of her Withered winds to avoid the brunt of her damage dealing. Damage dealer characters should try at landing a hit in order to hinder Oranomonos' attempts at casting Regrowth to stop the spell from healing herself. Tanks must be able to stand up to Implant many times. This is why they must be aware of how the effect is stacking and change as necessary.

Healers are particularly useful against Oranomonos as players who are together in a team will want to to have at least two. Healers should dispel their Rapid Growth effects from their colleagues. If Oranomonos begins to use Dirge of the Fallen Sanctum, all players should be grouped together so that the healer is able to use their strongest AoE healing capabilities on everyone. It is also recommended to use  buy WOW WoTLK Classic Gold defensive cooldowns when they are grouped together so that they can better stand Oranomonos attacking.