Espa Roba, known as Esper Roba in the manga and Japanese version, is a Duelist who claims to have ESP. In reality he is a fraud who uses his younger brothers to spy on and reply back to him the cards in his opponent's hand, thus allowing him to 'predict' the opponent's strategies almost before they perform them.
Espa made his first appearance in a cameo in Battle City and has made several ever since.
Espa was a young Duelist who entered Battle City to uphold his reputation and protect his younger brothers. He was first shown defeating Rex Raptor and taking "Serpent Night Dragon". Rex advised Joey Wheeler not to Duel Espa on the grounds that his psychic abilities allowed him to read all the cards in his hand. With an air of self-confidence, Joey accepted the Duel.
Although Espa initially gained an advantage due to the fact he knew what cards were in Joey's hand and on his field, Joey inferred what was happening and attempted to confuse his watchers from above by putting the cards "Skull Dice" and "Graceful Dice" close to each other.
Mokuba Kaiba eventually discovered the source of Espa's "psychic" abilities; his brothers spied upon Joey's hand from upon a high rise building. However, the brothers pleaded with Mokuba to let Espa continue with the Duel, stating that he was a strong Duelist despite his cheating ways.
The psychic front was to build an impression of an unbeatable duelist and thus deflected any abuse that was usually heaped upon Espa and his brothers, they were heavily bullied due to being carnival folk before. To Mokuba, this situation paralleled his brotherly relationship with his older brother, Seto and he let Espa continue the duel. Due to this, Espa's psychic reputation was tarnished, but he continued his duel with Joey nevertheless.