How To Complete The Wellspring: Defend Activity in Destiny 2: The Witch Queen

gamespot.com:

The Scorn are still a threat to Guardians in Destiny 2. In Savathun's queendom, the Scorn are after a source of Light inside the Wellspring--which distributes Light across the Throne World, and Guardians need to protect the Light from the Scorn’s ruinous plans with the Darkness entity. Although this activity deals with the Scorn, an earlier image from Bungie showed players attacking the Hive. Right now, it's unclear if this activity will change in later weeks or at higher difficulty levels.

The Wellspring: Defend is the new six-player, matchmade activity in the Court of Thorns area of Savathun’s Throne World--the recommended Power level is 1510. Players can access it after completing The Witch Queen campaign and additional objectives.

An Exotic quest, called Of Queens and Worms, will direct players to speak to Mara Sov at the Enclave. After meeting with Mara, play through the Birthplace of the Vile strike and visit Fynch. Fynch will give you The Spring of Power quest to complete the Wellspring activity--Of Queens and Worms branches into another quest at this point.

First, players need to charge the Wellspring at the center until the number reaches 100. It’s kind of like those public events where Guardians need to stand on platforms to charge it up. It doesn’t hurt to move around the map a bit, but staying at the center is the best spot since there will be multiple waves of Scorn spawning everywhere. Melee weapons and medium-ranged weapons do well in this activity. Also, players can use rally banners before each encounter--there are three encounters total.

After charging up the Wellspring, push forward and activate the next area. Here, players will need to shoot the Pyramid Spikes to destroy the Cruxes and defeat Scorn.