Darth Ruin, formerly known as Phanius, was a male Umbaran who reigned as a Dark Lord of the Sith at the beginning of the Draggulch Period in around 2000 BBY. Previously an esteemed Jedi Master, Phanius gained notoriety within the Jedi Order due to his prominently self-centered philosophy—the idea that his very will superseded everything in existence. At odds with the Jedi tenets, Phanius eventually abandoned the Order in pursuit of his individualistic ideology, steering him towards the dark side and leading him on an alternate path—the way of the Sith.

Intent on reviving the Sith into a new empire, Phanius rallied various surviving Sith clans under his banner. The former Jedi Master then declared himself a Dark Lord of the Sith under the new identity of Darth Ruin, simultaneously converting fifty additional Jedi in the Fourth Great Schism. Finalizing the Sith resurgence, Lord Ruin gave rise to a galactic-scale conflict—the New Sith Wars—against the Jedi Order and the Old Republic.

The reign of Darth Ruin met an untimely end due to the Dark Lord’s own ruthless egomania, evoking the wrath of his Sith disciples and resulting in his assassination. In spite of Ruin’s death, his machinations left behind an enduringly bloody legacy; the Sith crusades—while frequently plagued by disagreement and backstabbing—continued for a millennium in his absence, bringing galactic civilization to the brink of collapse.

Darth Ruin was first mentioned as an unidentified Jedi Knight-turned-Sith in the novelization of The Phantom Menace, written by Terry Brooks and published in 1999. The book incorrectly cites Ruin as the original founder of the Sith Order as a whole. In 2000, this error was corrected in The Essential Chronology, establishing the still-unidentified Ruin as the creator of a successor faction—the New Sith. The character was officially named Darth Ruin by author Abel G. Peña in Vader: The Ultimate Guide, a limited edition magazine released in 2005. To this end, Peña saw the name Ruin—derived from the Latin word «ruīna», meaning «fall»—as a fitting representation of the character’s fall to the dark side, as well as the destructive chaos following his demise. Several other Darth titles were considered, such as Reaper, Fatalis, Necro, Mortalis, Eradicus, Execute and Solopsis. While creating Ruin’s backstory, Peña envisioned him as an intelligent, wise and evil individual in the same vein as Dooku from the Star Wars prequel films, as well as Darth Traya from the video gameKnights of the Old Republic II. In 2006, Peña further expanded Ruin’s history in an article titled Evil Never Dies: The Sith Dynasties, confirming his species and former identity as a Jedi Master named Phanius.