"He pushes the bulk of his Light into his weapon, spreads its influence to reach the nearby Redjacks, and reignites his gun before touching the barrel to the ground and firing. The ground bubbles with hot magmatic Light; a warmth envelops the Redjacks as Solar flame imbues and empowers their rifles with golden power. Shaw directs the firestorm of golden Redjack rifles to incinerate every last charging foe." From "The Swarm" Lore Tab. Give us this Bungie :)