Cloakers and ooglith masquers were the two branches of the family of biotechnological bodysuits worn by the Yuuzhan Vong. Like all Yuuzhan Vong equipment and devices, these were living organisms: in effect, they functioned as a second skin for the wearer.
The cloaker was a form of quasi-protective clothing, typically worn in situations where something more durable than robeskin was required, but where the heavy protection of vonduun crab armor was not needed. A masquer, on the other hand, was a disguise that enabled a Yuuzhan Vong to conceal their true identity, typically by impersonating a member of another species. In keeping with the importance of ritual and caste in Yuuzhan Vong society, however, some versions of both cloaker and masquer had significant connotations in the spheres of symbolism and status; indeed, it appears that the original development of the masquer was for use in religious ritual before being adopted as a means of disguise.
Ultimately, though, these differences between varieties cloakers and masquers were primarily to do with their external surface, and the basic biology of all varieties was the same. They were usually tight-fitting full-body garments, donned by laying them on the floor and stepping inside them. The cloaker or masquer then began to form itself around the wearer's body, beginning at the feet, and securing itself to its host by inserting tiny cilia through the pores of his or her skin—a sensation which was painful.
Once donned, the bodysuit could be worn for long periods of time. When the host wished to remove their masquer or cloaker—a process every bit as painful as putting them on—they triggered the creature by stimulating the seam where it sealed, which on hooded versions usually ran upwards from an opening at the lips to the side of the nose.
The most basic variety of cloaker was a sleek black bodysuit, which could be issued even to slaves. It is probable that this was no different than the ooglith, which in other circumstances provided a hood for the wearer's head and a transparent mask across the face. While flexible and form-fitting, the ooglith cloaker also functioned as a highly effective protective suit; paired with a gnullith breather, an ooglith was proofed against the pressure, atmosphere and temperature differences of most dangerous environments, such as deep water, but for use in the vacuum of space, a special vacuum ooglith was used, a rust-red variant worn along with a lungworm to give an air supply for the gnullith.
The cloak of Nuun, worn by the elite Hunters of the warrior caste, was a variety of the ooglith cloaker. This was a bodysuit with an external covering of photosensitive cilia, which visually garbed the wearer in a near-flawless image of his surroundings, in effect a personal cloaking device.
Another variety of cloaker was the oozhith worn by members of the Shaper caste. Like the cloak of the Nuun, this had cilia on the outside as well as the inside, which sought out and fed on microorganisms in the air, creating a subtle shimmer to the surface as they moved. The full-body oozhith was only worn by Master Shapers, however, with Shaper Adepts wearing a sleeveless version that ended above the knees. The oozhith had a small pouch for equipment.
A relative of the cloaker species, the masquer was designed for disguise. The basic ooglith masquer made the wearer appear Human. Before the start of the Yuuzhan Vong War, Nom Anor spent most of his decades-long reconnaissance mission in the New Republic and Imperial Remnant wearing masquers of this sort. The thought of being disguised as an infidel for so long would later prompt a rare emotion, close to pity, in Warmaster Tsavong Lah.
Ooglith masquers were subsequently adopted by other scouts like Yomin Carr, and by the time of the attack on Duro in 27 ABY, Nom Anor had developed a variation known as the gablith masquer, which disguised the wearer as a non-Human alien. Gablith masquers were known for both Duros and Givin, and in contrast to the Yuuzhan Vong and almost all their biots, a Duros gablith masquer could be sensed in the Force; indeed, it could at least partially mask the Force void of its Yuuzhan Vong host from the senses of Jedi. The only other creatures used by the Yuuzhan Vong known to have had a similar Force presence are those like Chazrach and voxyn, which were derived at least in part from species that were not part of their original genetic stock, suggesting that the gablith masquer may have made use of bioengineered Duros tissue. By 29 ABY, a type of masquer had also been created which allowed a Yuuzhan Vong to impersonate a reptilian Ssi-ruu, a process that involved dislocating limb joints and contorting their bodies agonizingly to imitate the theropod physique of the Ssi-ruuk.
Other masquers, perhaps the oldest variety, simply hid the wearer's true face behind another Yuuzhan Vong visage, often visibly recognizable as a mask. During the period of the Yuuzhan Vong invasion, this remained a fashion among the Praetorite Vong, although it had fallen out of favor with the Shaper-caste domains decades earlier. Onimi wore a masquer to disguise his shaming in his guise as Kae Kwaad, whereas conversely, Nom Anor wore a masquer bearing the features of a Shamed One in his role as Yu'shaa.
A Yuuzhan Vong creature called an unmasker was designed to detect a masquer and to force it to peel back from its wearer's skin.
By 44 ABY, Wraith Squadron member Viull Gorsat had bio-engineered what he called "neoglith masquers" from genetic material found in this galaxy. He was able to craft custom masquers disguising himself and other members of the squadron as other humans, including a perfect copy of General Stavin Thaal, and a fictional species created from crustacean genetic samples found on Kuratooine.