The Clipse were once a more peaceful technological race. However, following their centennial anniversary of global peace, an unknown alien threat unleashed a gamma-ray burst that wiped out their technology, killed everything on their planet's western hemisphere, poisoned the atmosphere, and burned a "signal" into the asteroids and comets of their solar system. The resulting collapse of civilization was complete.
As the Clipse rediscovered subsistence agriculture, the marked asteroids began to rain ceaselessly down on the planet, "seeding" it with hostile alien life. In order to combat this new enemy, the Clipse were forced to militarize in turn. As such, thousands of years after the collapse, the Clipse had become an extreme martial culture that worshiped guns and "knew only war", with the planet an eternal battleground between them and the invasive alien ecoystem. Their moon, Kaga-Clipse, became their military capital, bristling with interceptors and defenses.
Under the reign of Emperor Calus, the Clipse were absorbed into the Cabal empire. They grew to be one of Calus's favorite member species. Believing their condition of eternal war to be an unalterable fact, Calus provided aid in the form of high culture and luxuries in an attempt to enrich their brutal society. The Clipse did not appreciate his gifts.
After Dominus Ghaul's coup, he attempted to earn the Clipse's loyalty by sending military aid to their embattled planet. His efforts only succeeded in poisoning it and its people, its hostile ecosystem proving too resilient to destroy without also destroying the planet. After a century of failure, Ghaul decided he was wasting his resources and abandoned the Clipse and their world.
In exile aboard his Leviathan, Calus discovered them again. He invited the Clipse to join his Loyalists, and they attempted to shoot him down with missiles. Rebuked, Calus turned to conquest. Kaga-Clipse's guns and interceptors proved no match for his gigantic starship, and he landed 6,000 troops on Kaga-Clipse itself, led by a Shadow, Valus Nohr. The campaign to capture the Clipse moon lasted for eight weeks. Towards the end, the Clipse had trapped Nohr in her own bastion, only for her to break out and destroy their forces on her famous "thunder run," calling down missile strikes from the Leviathan against vital command posts. 
Desperate, the Clipse gathered their greatest warriors and launched a commando boarding action against the Leviathan. Only Rull survived to reach Calus's throne room, bloody and exhausted, where the Emperor casually offered him refreshment and alliance. Bemused, Rull accepted.
His victory secured, Calus rewarded the Clipse surrender, first by bringing thousands into arcologies aboard the Leviathan to live the rest of their lives in his trademark opulence, and second by winning their perpetual war: incinerating their planet and all life on it with Kaga-Clipse's own guns. 
List of appearances
- Bungie (2017/8/9), Destiny 2: PlayStation 4, Activision Blizzard, Mask of Rull
- Bungie (2017/8/9), Destiny 2: PlayStation 4, Activision Blizzard, Imperial Shadow's Cloak
- Bungie (2019/6/4), Destiny 2: Season of Opulence, Playstation 4, Activision Blizzard, Lore: Entry VI
- Bungie (2017/8/9), Destiny 2: PlayStation 4, Activision Blizzard, Chassis of Rull
- Bungie (2017/8/9), Destiny 2: PlayStation 4, Activision Blizzard, Greaves of Rull
- Bungie (2017/8/9), Destiny 2: PlayStation 4, Activision Blizzard, Gauntlets of Rull