25 years ago - Tara Markov is born the illegitimate daughter of the king of Markovia.
20 years ago - 5-year-old Tara is given over to Dr Helga Jace who helps activate her metagene & strengthen her latent geomorphic powers.
15 years ago - 10-year-old Tara is sent away to live with her mother in America.
13 years ago - 12-year-old Tara runs away from home & becomes an underage mercenary & assassin.
Terra has a very specific role to play in the history of the Teen Titans. Her infiltration and betrayal of the team are legendary, and everything we do with the character needs to support that moment. Her relationship with Deathstroke and with the Titans are core to one of the best arcs in the team's history, so much so that we're ensuring that her betrayal is key to the actual downfall of the team.
There have been several other characters by the name Terra, most of them pale imitations of the original (literally, on one case. she was a clone). Atlee, the Terra from an underground civilization of geomorphs wound up a sidekick to Power Girl and was a fun character, but trying to work her into continuity meant trying to explain that underground civilization, and they never did explain why this totally separate character would suddenly be using the same name as the Titans infamous betrayer. We'll only be using the original character.
Interestingly, It was damn near impossible to find images of Terra's traditional costume, because google was completely filled with images from the animated series version of the character. Her animated costume is a solid one, and is clearly very popular, so we'll go with that one.