Suna's twin, Raymond Diaz had linked up into one of the captured Mad-Ones. He claimed at the time he was gathering Intelligence. He'd never been the same again, he was disowned as a result and thrown on the otherside of the Civil War. His unstable personality could have been a result of this link up. The Mad-One involved was the first man Suna had ever killed. The war was not over land or beliefs, but hardware.
Shereighians are a species that have integrated bio-technology into their lives. Shereighians give crystalline matrixes to worthy hosts, it attaches to recipients hypothalamus. These hosts must be emotionally and intellectually strong, but usually those who could afford it. The matrixes act as personal computers for the recipients allowing them to store data, theories, ect. they can also use the matrix to calculate, utilize, interact and extract information from other sources.
However the Ferengi developed and imitation matrixes, and flooded the market with these cheaper products. It was discovered too late that the owners of these matrixes were driven insane after a month. The slaughter began, as the Mad-Ones began to kill all, including friend and family who had no matrix or a normal matrix. In the end, close to a million corrupted Shereighians were killed and Daimon Moran and Nagus Merrot long gone.
Suna hadn't seen combat until a few days before that Mad-One had been captured. The Twelve year old Engineer killed her first man that day, the one her brother had linked with. Raymond himself managed to flee to Earth and was granted asylum, and avoided the slaughter that claimed 900,000 others. Though it all, Suna rose in rank, and soon was a Platoon Leader of the 135 Squadron. At war's end, the Shereighian Democratic Body had no need of a Sixteen year old Platoon Leader, and discharged her from service. She broke up with Maylar around this time, but they remained friends.
She retuned to her studies, and soon got a Bachelor of Science at the Shereighian Science Academy and obtained Bachelor of Life-Sciences, and of Geophysics. When the Dominion War started, Suna decided to pause her accidemic career and switch to Starfleet Academy, and managed to gain entrance at age 16. After the Dominion War ended, the twice Child Solder settled in for two years of intense study and obtained her Doctorate in Mathematical, and Stellar Sciences, just before her 20th Birthday. She met Semaj Yarlig doing his Doctorate in Astrophysics at the same time as her.
Her years after graduating hadn't been that good. Because of her lack of a childhood and academic issolation, she was emotionally immature. She made some very foolish decisions. She tried to date, but her first boyfriend Robert Thompson defected to the Romulans. She on the origonal USS Impulse until the outbreak of the Tholian War.
During the Tholian War, Suna was back in her element. She was assigned to the USS Cairo A as the Cheif Science Officer. During her time on the Cairo she foolishly became involved with the infamous Captain Robert Carrington. He set aside so he could publically court Dr Bev, Praetor Neral's Daughter, to get Romulan Support for the war.
After, the devastated this Suna was recruited by a Think Tank, to help them in addition to her Starfleet Responsibilities. After the Dominion Fleet fled the Battle for Antilles Rift and the Tholian War ended, she deviced a trap to draw out the Dominion Fleet using her old ship the Cairo A and dear old Captain Robert Carrington as bait. Both plans worked, the Dominion Fleet was drawn in and destroyed and the Cairo A was destroyed. Carrington didn't die, but did vanished afterwards.
Suna's work with the Think Tank had her traveling all over doing scientific tests for them. After the Think Tank found out the location of the Ferengi behind the Sherighnian Civil War, she leaked the information to the New Maquis and Daimon Moran and Nagus Merrot were killed.
Her work made her a target of The Majician, an assassin who was also full of cybernetics. They fought across the Australian Outback, but the The Majician got the better of her with his advanced weaponry and Suna Diaz was killed.
Sighting of Suna following her death had been made, but nothing verifiable. Rumor has that she is still working under the radar for the Think Tank.