What wielding the darkness could mean for Guardians in Destiny 2: Beyond Light

“The line between light and dark is so very thin.” - Uldren Sov.

Eris Morn is the exception to the rule. Lost in the depths of the Hellmouth on the Moon for years after her fireteam's failed attempt to assassinate the Hive god Crota and losing her light, Eris - guided by the whispers of her Ahamkara bone - navigated the depths of the moon and learned to wield the Hive's dark magic herself whilst remaining herself. 

Can the Darkness be defeated? There is a theory held in some Warlock circles that the Light and Darkness are two sides of the same coin, and both necessary forces of the universe. The Light, life and creation. The Darkness, death and entropy. Warlock Ulan-Tan's theory of symmetry attests to this. 

"Therefore, I conclude: the reason you persecute me is not because of the symmetry. It's because of the truth beyond the truth, the truth which you must dread: if we could destroy the darkness, but we had to give up our Light to do so, how many of us would make that trade?" — Ulan-Tan

There are even bigger questions we must ask ourselves of the consequences of wielding the power of Darkness, if we take up the power of the eternal rival of the Traveler, will it forsake us?

We know that the Traveler once blessed the Fallen with it's light, and forsook them, leaving them to the destruction of their home worlds. While the Traveler awoke at the conclusion of the Red War after centuries of slumber, it has remained silent, just as the Darkness reaches out to us.

Beyond Light carries a theme of breaking free. The Hive god of war and sister to the late Oryx the Taken King searches for a way for the Hive to free themselves from their dependence on the Worm god's for their connection to the Darkness.

The Fallen seek to end their dependence on ether, maybe we as guardians will break free of the binary way in which we understand the paracausal powers of the universe.