Nava Bashevis was orphaned at a young age thanks to a terrorist attack in her home city of Tel Aviv, Israel. The soldier who rescued her from the rubble, moved by the child’s tragedy, adopted her. And though she was brought into and raised in a loving home, the trauma of her loss continued to linger. Nava became a strong-willed and determined young woman, and her father assisted her in directing her anger into constructive exercises rather than allowing her to be consumed by it.

Upon graduation, Nava attended university in the United States before further continuing her education at England’s prestigious Oxford University, where she earned her doctorate in international law. Upon her return to her native Israel, she immediately enlisted in the Mossad, and became a high-valued operative.

During an operation in an undisclosed location, Nava and her unit were assigned to investigate rumors of a terrorist cell utilizing an exotic and potentially dangerous power source. Once they covertly penetrated the facility, they were

astonished to see what appeared to be nothing more than a strangely-glowing staff hooked into the central power core of the facility.

It was then that their luck ran out, and the terrorists discovered their presence. Nava's unit was quickly engaged, and though the firefight was brief, it was intense. Though casualties on the terrorist's side were heavy, Nava's entire group had been either killed or wounded. With enemy reinforcements approaching, Nava decided to detonate the apparatus, killing them all, rather than allow them to use the strange power source for whatever next attack they had planned.

Planting the explosive charges around the room, Nava grabbed the rod and attempted to pull it free. However, once she came into physical contact with it, an amazing transformation occurred. Energy flowed from the device into Nava's body, transforming her even as the explosives detonated and destroyed the entire facility. Miraculously, Nava survived the conflagration, and emerged from the rubble unharmed, much to the surprise of the responding rescue workers. With staff still in hand, Nava quickly made her way back to Mossad headquarters.

Upon her return and debriefing, Nava underwent a series of tests determining the extent of her newfound abilities. It was then decided that her role should be expanded, and that she become a hero for the Israeli people. Given the code-name Onyx (due partially to the fact that she shared a physical durability similar to the mineral), she continued her war against terrorism both in Israel and abroad. And after several years of operation, she was invited to join the latest incarnation of the storied First Guard team.

Onyx served with The First Guard with distinction for years, and became one of the most visible and respected members of the team. Her fierce personality, independence, and dogged pursuit of women’s rights across the world made her an icon. And though she was often rumored to be romantically involved with her teammate American Eagle III, the two were never more than comrades-in-arms.

Onyx was present at The First Guard’s headquarters when the invasion now known as “The Decimation” began, destroying the base, and killing or capturing many of her teammates. Along with many other heroes, she was later freed and aided in repelling the alien invasion of Earth.

Following the invasion, Onyx returned to Israel to aid in its rebuilding. And after a time, she was approached by the American hero known as The Fighting Yank and asked to serve in a reformed First Guard. Onyx agreed, and continues to serve to this day.

Onyx possesses vast superhuman strength, enabling her to lift (press) approximately 85 tons under optimal conditions.

In addition to her superhuman strength, Onyx possesses a high degree of invulnerability to physical harm, as well as superhuman endurance. She has been observed to survive direct hits with high-caliber artillery shells as well as powerful explosives without injury. Additionally, her superhuman endurance allows her to continue high levels of activity for long durations without exhaustion. Her reflexes have been augmented as well, allowing her the speed to deflect incoming projectiles such as bullets with her staff.

Onyx also possesses the ability to fly. She is capable of reaching speeds in excess of mach 2 in a planetary biosphere. In space, she is capable of greater speeds due to the absence of an atmosphere.

Although she possesses great physical powers, Onyx's body still requires food, water, and air, as well as sleep, though she can go for longer periods without these than a normal human.

Onyx’s main offensive weapon is the staff she carries. The staff is of unknown manufacture, and has baffled any and all attempts to ascertain its composition and origin. Though she was required to maintain contact with it in the beginning to keep her superhuman abilities, the change has since become permanent and she can release it without consequence.

The staff possesses the ability to generate a high-intensity beam of energy capable of unbinding the ties of an object at a molecular level, essentially disintegrating it. It can also generate light, as well as be used as a shield to deflect incoming objects. To date, the staff has proven to be unbreakable.