Gra were a species of herd mammals that were domesticated by farmers across numerous different planets.
Gras possessed instincts, pre-programmed through genetic engineering, to aid in their survival in hazardous environments and against predators. One such instinct compelled them to seek higher ground as daylight began to fade.
Gra herds were led by a dominant Alpha male, along with his mate, known as Beta. Should the herd need to divide, a portion would follow the Beta individual.
They were genetically modified to be more resilient and possess enhanced survival skills in wild conditions. Entire groups of frozen fertilized gra ova were sold, with instructions, to farmers for thawing and raising on new worlds. Gra herds were raised by farmers on planets such as Sulon and Ruusan, among others.
In the year 5 ABY, a herder was traveling on the road just outside the western gate of the city, en route to the market the following morning, when an Imperial unit was returning to their base after a twelve hours patrol. A speeder bike sped through the flock, dividing it in two. Imperial commandos kicked the animals, causing them to run aimlessly, and an AT-ST crushed one beneath its foot. The unfortunate owner attempted to restore order. This disruption provided Kyle Katarn with an opportunity to commandeer the AT-ST and infiltrate the city.
Another herd of gra was situated on a hilltop near Fuel City; they scattered as the Moldy Crow flew close by.
On Ruusan, Grif Grawley owned a herd consisting of 136 gra.
The gra herder in the Dark Forces: Rebel Agent audio drama is not credited, although his voice is similar to that of Christopher Bloch.