Nearly two meters tall, the YVH 1 droid was built on a reinforced humanoid-type skeleton and protected with layered, self-healing black-gray laminanium armor that resembled the voduun crab armor used by Yuuzhan Vong warriors. The skull-like head, glowing red photoreceptors, and external circuitry furthered the Vong-like appearance of the droid, which earned them the moniker "Yuuzhandroids". This was meant to demoralize and anger the Yuuzhan Vong warriors, as explained below, making them more prone to mistakes. Their war cry, however, was definitely programmed to drive the Vong mad. YVH units were specifically instructed to maximize the enemy loss ratio while minimizing friendly casualties, and used the phrase "maximum efficiency" to praise one another on this skill.
The droids included advanced search-and-identify programming that could penetrate ooglith masquers to sort civilians from Yuuzhan Vong. This programming proved essential in rooting out Yuuzhan Vong sleeper agents and hidden provocateurs. Once identified, the YVH 1 could engage enemies with its right arm's variable-output blaster cannon or the weapon attached to its modular left arm, which was often a heavy laser cannon, sonic rifle, or projectile launcher. Specialized versions of the YVH 1 droids were created, including adaptable camouflage droids, aquatic versions, and miniature versions fitted into the shells of MSE-series droids for espionage. In addition, certain versions were capable of making use of baradium pellets that dealt a high degree of damage to Yorik coral. It was an optional quality for laminaium to be introduced into the droid though it enhanced the endurance of the war droids in combat if used. This armor was capable of taking a plasma cannon blast from a Coralskipper in the chest and still survive though the laminanium ignot would need to be replaced after such engagements.
After a series of successes, newer YVH 1 droids were modified to include a vocoder package—which mimicked Lando Calrissian's voice—of war cries, taunts and insults in the Yuuzhan Vong language. Lando, founder of Tendrando Arms, was particularly proud of the taunts that proclaimed the YVH 1 superior warriors to the Yuuzhan Vong—a powerful insult considering the Yuuzhan Vong's intense hatred of machines and automata.
The droids' Vong-like appearance, appropriate taunts, unique programming, and incredible combat effectiveness made the YVH 1 a walking blasphemy and strong demoralizer to the Yuuzhan Vong. Since the Yuuzhan Vong had a strong hatred of technology, the creation of these droids proved to be an efficient and creative method of demoralization.
The first YVH 1, whose prototype, YVH 1-1A, was designed by Lando Calrissian and produced by Tendrando Arms was activated in 27 ABY, two years after the Yuuzhan Vong War began. This prototype was involved in a weapon's demonstration on Coruscant with Chief of State Borsk Fey'lya, General Garm Bel Iblis and Wedge Antilles in attendance alongside Leia Solo and Han Solo. After the droids demonstration, it detected the presence of Yuuzhan Vong infiltrators and whilst its weapon systems were deactivated, it managed to aid in the elimination of the enemy agents before they could assassinate Chief of State Fey'lya. This helped secure production of the droids and they began to see service in the war against the Yuuzhan Vong invaders.
YVH 1 droids served the New Republic and its successor government, the Galactic Federation of Free Alliances, in many battles. Their first mission deployment was the Mission to Myrkr where they assisted the Jedi Myrkr strike team with the infiltration of a Worldship that was breeding the Voxyn. In addition to that mission, YVH 1 droids were involved with the Fall of Coruscant, the occupation of Borleias, and the Liberation of Coruscant.
After the war, the YVHs were used as body guards or for heavy assault. Lando gave a customized YVH 1 named Nanna to the Skywalkers as Ben's personal defender, and another to the Solos. Tendrando Arms also built a set of customized YVH 1 droids, called YVH 5 Bugcrunchers, for use against the Dark Nest.
YVH droids were also used by Corellian officials in 40 ABY, such as Thrackan Sal-Solo and Aidel Saxan during Operation Roundabout. Sal-Solo's droids attempted to kill Jacen Solo aboard Centerpoint Station, while Saxan's droids were used as decoys to kill Jaina Solo, Zekk, the Falleen Jedi Thann Mithric, and the Bothan Jedi Kolir Hu'lya.
While on an investigation of the Ducha AlGray's Hapan estate, Jaina Solo and Zekk were attacked by two YVH 1 droids in the possession of the Ducha. However, even two of the deadly droids were not able to defeat the pair of Jedi.
The YVH 1 was also the basis for SD-XX, Jacen Solo's security droid.
Some fans have pointed out that the YVH 1's skeletal appearance looks quite similar to the automatons from the Terminator movies. However, this could be a coincidence, as the YVH droids were designed to look like the Yuuzhan Vong, who also have a very skeletal appearance.
The YVH 1 shares several characteristics with the SD-10 battle droid introduced in the Dark Empire comic series, such as self-healing metal alloys and the capability for tactical innovation. No direct link has been suggested, but it seems likely that the SD-10 was among the droids studied and improved upon by Tendrando Arms in creating the YVH.