“Defeat the Vex threatening the Burning Forge.”
For this part of the mission Boundless Light is active. You have a rapid recharge on your Super. Head around the map and clear out all of the Vex that you encounter. You will be getting a lot of Super kills, Orbs of Light and Solar Kills. Enjoy the boundless power and get more familiar with your new Subclass's Super. Clear out the Vex and you will complete the mission.