Zandar is wholly dependent on his twin sister Zarana. As a teenager growing up on the streets of London, he found himself abused and beaten due to his small size, and in response he found himself with a unique talent for stealth and fading into the shadows to keep away from his tormenters. After the siblings joined up with the Dreadnoks, an Australian biker gang, Zandar has used the gang's stolen holographic technology to enhance his skill at remaining unseen even further and picked up a custom spear-gun weapon to defend himself with; despite this, though, he's still emotionally reliant on and endlessly loyal to his sister.
- "We do not need to hear your life story."
- "Your life story we do not need."
- "Your money will suffice."
- "Just give us your money."
- -Zandar and Zarana, "Threat Matrix, Part 2 of 4"
Born into poverty in London, Zack and his twin sister Zoe grew up in an abusive orphanage, refusing to speak to anyone but each other. Out of fear of being separated from each other, the two fled the orphanage as teenagers, making a life for themselves on the street by begging, stealing and pulling hustles; living on the street, Zack regularly took abuse and beatings when Zoe wasn't around to protect him, and honed his stealth skills in response. Eventually, however, the twins fled to Australia using tickets bought by Zarana's admirers in order to escape arrest by the London police; on arriving, the two soon fell in with the vicious Dreadnoks, taking on the names Zandar and Zarana and making use of their stolen technology to enhance their particular skills.
Some time after the Dreadnoks' leader Zartan abandoned them, Zarana and Zandar travelled to New York City to engage in an arms deal with the biker gang known as the Heathens on Randall's Island on the instructions of "the One". This was picked up by G.I. Joe's Threat Matrix program, leading the team to interrupt the deal before the twins recieved their payment. The two fled on their custom Dreadnok motorcycle, which contained holographic technology that they used to turn themselves invisible to evade the Joes, but explosives fired at them by Duke disrupted their cloaking and made them visible once more. The twins attempted to fight back, but Quick Kick knocked them out with his nunchaku, allowing them to be arrested by the Joes. In the aftermath, it turned out that the weapons that the Dreadnoks were selling to the Heathens were worthless junk, though they protested that they had done exactly as "the One" instructed them.
At some point, the twins reunited with the other Dreadnoks, and were eventually approached by Crystal Ball, a member of Cobra High Command, who sought to use the gang to help him take over the Inner Mongolia region of China; the Dreadnoks agreed in order to establish their own "outlaw nation". In order to lure the G.I. Joe team to Crystal Ball's headquarters, the twins disguised themselves as the native Mongolians "Ying" and "Yong"; though Cover Girl was suspicious of their British accents, they managed to bring the Joes to the Dreadnoks' manor, where the rest of the gang ambushed the team; while the Dreadnok heavies engaged the Joes, Zandar and Zarana slipped out. After the G.I. Joe team escaped in a jeep hot-wired by Cover Girl, the Dreadnoks pursued them on their motorbikes, with Buzzer riding in Zarana's sidecar. The Dreadnoks were fended off by the Joes' resident Transformer Skywarp, at which point the earth started shaking and split open; though Zarana and Zandar recognised what was happening and ordered the others to retreat, the gang were all grabbed by a "Fatal Fluffy" when it emerged from the ground, dragging them in. As Zandar was pulled under, he begged his sister to help him.
The Dreadnoks managed to escape from the monster, as the Fatal Fluffy "didn't like the taste" of them. When a United States army transport taking the Baroness and Crystal Ball to the Hague was attacked by Cobranarchists, Zandar pretended to be a civilian trapped by rubble from the anarchist's bombs, with Zarana calling for help. When Duke ran over to rescue him, Zarana knocked the ex-Joe to the ground with a bladed weapon, and the Dreadnoks prepared to take custody of Duke's prisoners.
- In classic G.I. Joe media, Zandar and Zarana are the siblings of Zartan, something not really possible in IDW continuity thanks to Zartan's esoteric origins.
- The two being English comes from the G.I. Joe: A Real American Hero cartoon, where the Dreadnoks — characterised as an Australian biker gang — were inexplicably portrayed with Cockney accents.