Terra's powers are currently limitless: while she limits herself to harmless feats as growing large formations of rock with the slowness needed to avoid a geological hazard and using floating rocks as projectiles and to levitate around, Gerard Shugel, the Ultra-Humanite, while residing in her body was able to shift nearby tectonic plates with ease, or cause vulcans to erupt at his will: he surmises the Terra has always had those amazing amount of power, but willingly choose to limit herself in fear of the damage she could deal.
Terra Markov, half-sister of Geo-Force, Brion Markov, was the illegitimate daughter of the King of Markovia. While in Markovia, she came under the care of a Dr. Helga Jace, and through her experiments, Terra obtained Earth manipulation powers: specifically, the ability to control all forms of earthen matter. After obtaining these powers, she left Markovia for the United States. Unlike her more heroic brother, Geo-Force, Terra had deep-rooted psychological issues, believing that, with their powers, they should rule Earth rather than help the weaker masses. As a result of this belief, Terra became a mercenary, doing dirty work for others such as Deathstroke the Terminator (with whom she shared a romance, despite being fifteen years old). She joined the Teen Titans, fooling them by staging a battle versus Deathstroke. She then operated as a spy for Deathstroke, eventually giving him the information he needed to kidnap the Titans, with no regrets.
Eventually, the captured Titans were held in a stronghold of Deathstroke's contractors, The H.I.V.E. Nightwing — who had recently retired from his career as Robin and created the Nightwing identity based on stories Superman had told him of a Kryptonian hero — and Deathstroke's son, Joseph William Wilson, alias Jericho, raided the complex to rescue them, but were captured. When presented to Deathstroke and the organization in general, Jericho possessed his father and freed the Titans, who then attacked the H.I.V.E. Not knowing of Jericho's powers, Terra believed Deathstroke to have turned against her. In retaliation, she went berserk and fatally pulled the whole H.I.V.E. complex down upon herself while trying to kill Deathstroke. Despite her betrayal, a statue of her was placed in the memorial in Titans Tower. Her betrayal was never made public, with her brother simply being told that she had died in battle. Subsequently, Batman eventually revealed the truth to him in an issue of Batman and the Outsiders, prompting Brion to change his costume to green and gold, as he considered the original brown and orange too similar to the outfit worn by his sister.