Lancer first appeared in "Heroes Reborn:Doomsday" #1 (January, 2000). Samantha Dunbar was supposedly a normal New Yorker of Counter-Earth Franklin. She was married and have an unnamed number of relatives. She and her family were involved in a sailing race around Long Island when the Dreaming Celestial attempted one of his experiments on her planet. A tidal wave engulfed her boat and the entire city. The Atlantic coast line was decreasing in elevation for about 200 feet. She survived the flood by chance, her family were not so lucky.
She was one of the relatively few survivors of the incident.
Months later one of the "heroes" who had vanished just before the incident re-appeared, Dr. Doom. He fell into the water and would drown but Samantha dove in after him. She had to rescue him from attacking Atlanteans but was able to breathe enough air into his lungs for the man to recover and carry them both to safety. She had lost enough air for Doom to have to revive her. As soon as she woke up, Samantha demanded answers on what had happened to her world. Doom offered them freely and gained her partial trust. He needed an ally and confidant, she would do. Doom waited for her to go to sleep later that day. Then he injected her with nanites which granted her superpowers. She was rather furious because Victor had not asked for permission. However she saw him as the only one able to restore order to her world and agreed to serve as his Lancer, "someone to watch his back". She has mostly served him loyally ever since.
Lancer has demonstrated exceptional intellect, tactical skills and insight. She has enhanced human reflexes and muscles.Her powers manifest in the form of lances consisting of raw nuclear plasma. She can throw them at her opponents, increasing or decreasing the force involved at will. She is thus able to adapt the force needed to the situation at hand. She can also manifest plasma "claws", manifesting in her fingers and able to cut through material. Lancer has demonstrated near-immunity to energy attacks, including forms of radiation and magic. Her body needs a few minutes to adapt to the attacks, slowing her down for a bit.
The nanites inside her body are directly linked to Doom's data networks, allowing her immediate access to information stored in his files and programs. This works both ways, as Doom can use the link to monitor and analyze her actions. Doom has taken the time to teach her the Atlantead language through her nanites. Uncertain if she can also learn aditional skills through the same process.