"Mantra is a man, he just has a
woman's body. It was from this dichotomy that Mantra sprang. From the major
theme--a switch in genders--came the minor theme of the series: a warrior who
must become a sorcerer, a slayer who must become a nurturing mother, a man who
has died hundreds of times must become a woman who can only die once. That's
the conundrum--and appeal--of Mantra."
- Mike Barr, creator of Mantra (1994 Ultraverse Collector Card)
1500 years is a long time. It's even longer when that's how long you've been a footsoldier in a war between two wizards, each vying for control over the other. Such was the fate of Lukasz, the eternal warrior, the man who would eventually become Mantra. His story begins in the year 451 A.D., when he was called into the service of the wizard Archimage against the evil wizard, Boneyard.
Archimage and Boneyard were brothers, and each was highly skilled in the ways of magic. However, where Archimage practiced white magic which draws its power from life, Boneyard was a master of death-aspected black magic. This difference of philosophies would eventually erupt into a centuries-long conflict between the two wizards, as Boneyard sought to control and enslave the people of Earth, people whom Archimage was sworn to protect.
This battle continued on for some time, but apparently came to a head in the year 451 AD during the bloody Battle of Châlons, where Attila the Hun invaded Gaul in alliance with Gaiseric, king of the Vandals. He was opposed by the Roman general Flavius Aetius, who had allied himself with Theodoric, the king of the Visigoths. Confronted with superior numbers, Attila resorted to sorcery, and allied himself with Boneyard. Impersonating Theodoric's son, Boneyard killed Theodoric using the Sword of Fangs. (As told in the Night Man #11. Theodoric would go on to haunt his armor for the next 15 centuries until eventually his spirit seized control of a suit of the Teknight battle armor created by J.D. Hunt.) It was during this battle that Archimage apparently took up arms against his brother and enlisted Lukasz and other knights into his service.
For over 1500 years, the "Twelve Knights of Archimage" battled against Boneyard and his men. Each side suffered losses, but the magic of the two wizards continually restored their charges to life when they were killed. Boneyard's men were simply restored to life; Archimage's forces were reincarnated into different bodies, "displacing" the soul of the new host. Perhaps as a further indicator of the differing philosophies of the two wizards, Archimage armed his forces with technology, whereas Boneyard's men favored sorcerous weaponry.
A balance of power was struck, with neither side able to gain supremacy over the other. As a result, this conflict might have continued on for centuries longer, except for the betrayal of Archimage by one of his trusted knights, Thanasi. Somehow coming into possession of Archimage's true name--his "word of power--Thanasi betrayed Archimage to Boneyard, in exchange for the ability to take over whatever host body he wished. Using this information, Boneyard easily defeated Archimage, and decimated his forces. In a final desperate attempt to thwart Boneyard, Archimage cast Lukasz into a body rich in sorcerous ability, and provided him with mystic artifacts which could be used to enhance those talents. That body belonged to Eden Blake, an attractive divorcee and mother of two young children.
To put it mildly, Lukasz was not at all happy with this arrangement.
Having been a chauvinistic male for over fifteen centuries, Lukasz detested his new body. However, cut off from Archimage's magic, he also knew that if death came in this new form, it would be permanent. On his/her own for the first time in centuries, Lukasz struggled to learn magic in the hopes of freeing Archimage from Boneyard. Uncertain as to who betrayed his former master, Lukasz reluctantly adopted Eden's identity as a refuge from Boneyard's forces and grudgingly adapted to his new lifestyle. As Eden, he soon took a position within Aladdin, a shadow branch of the CIA used to keep tabs on ultrahuman activity.
As time passed, Lukasz became more proficient in magic, and (again, reluctantly) took up the role of the Ultra-heroine, Mantra. For a long time, he railed against his feminine condition, detesting his female body and resenting the children he had been saddled with, constantly searching for ways to regain his lost manhood. Over time, however, he began to care for the children and eventually, out of love for them and respect for their mother, started to accept his new role.
It was about this time that the Ultraverse endured "Black September," a thinly-veiled attempt by Marvel comics to rewrite or remove characters they were uncomfortable with. During this cataclysmic event, Eden's son Gus inherited bizarre and unexpected magical powers, and fought Mantra, killing her. However, she was able to prevent her own demise by again returning to the Soulwalk, the area she used to visit between reincarnations. While she was eventually able to return from the Soulwalk, she did so at the expense of her magical powers, which were transferred to a teenage girl by the name of Lauren Sherwood.
After Lauren inherited the powers, Eden left for San Francisco to be near Gus, who had been captured by Aladdin forces. Leaving the Sword of Fangs in Lauren's care, she retained her other mystical artifacts, determined to find a way to restore her powers. Her last appearance in the Ultraverse indicated that she had traveled to other parts of the world in pursuit of this goal, meeting with various mystical figures and collecting magical artifacts.
[That's my interpretation of the story. If you'd like to see how some of the ways it's been told in the Ultraverse books, check out Mantra's Origin in Pictures.]