Geo - Force is the brother of Tara Markov , also known as Terra , of the Titans .
In one of their earliest missions , the Outsiders team up with the Teen Titans , who are led at the time by Batman 's sidekick , Robin .
Geo - Force is the brother of Tara Markov , also known as Terra , of the Teen Titans .
In one of their earliest missions , the Outsiders team up with the Teen Titans , who are led at the time by Batman 's sidekick , Robin .