Tosh likes to use a balisong. He has good endurance, is a skilled martial artist and has a high opinion of his telepathic abilities. He has a nihilistic personality and while there is some good in him, Tosh knows that he must always look out for himself in order to survive. Such a personality places him as a counterpart to Matt Horner. He claimed he would do anything to get the job done.
His accent tends to get more pronounced when he gets excited.
Gabriel Tosh was raised by his grandmother on the "mean streets" of Haji. There were no facilities to train his psionic abilities, which his grandmother believed was "voodoo". As a child, he himself believed this.
Tosh was conscripted into the Confederate Armed Forces, where they recognized his psionic talents. He seemed to vanish, and no records of him from this period are available. Rumors ran rampant in regards to his whereabouts. In reality, he had been conscripted into the Ghost Program.
The Ghost Academy
Tosh made the transition from Confederacy to Dominion, establishing himself as a hardcore supporter of the latter. At this point in his life Tosh was a passionate supporter of Arcturus Mengsk and the Dominion, believing that while their actions may not have always been clean or moral, the Dominion protected the people from the protoss and zerg and so was ultimately a force for good. In Tosh's eyes the ghosts, as the Dominion's elite warriors and assassins, were at the heart of the Dominion's war efforts and the most vital aspect of the war. During Tosh's time as a ghost, he grew close to Dylanna Okyl. However, the two drifted part, leaving Okyl resentful towards Tosh.
In 2501, Tosh served as the leader of the Ghost Program's Team Blue, a group of ghost trainees. A first-class trainee, he was slightly older than the other members of the team. The team system was a new innovation, and Tosh had to lead Team Blue for the first time in the Valerian hostage taking simulation with one position vacant. New teammate Nova Terra went off on her own. Tosh directed his other two subordinates, Kath Toom and Lio Travski, but both fell into trouble. Tosh decided to carry out the mission by himself, but without backup was "cut down" by his opponents. Preceptor Lagdamen criticized him on this point, saying bad teamwork was worse than no teamwork, and praised Terra for almost completing the mission on her own.
Dylanna Okyl, the leader of Team Red, repeatedly criticized Nova Terra for her lack of teamwork in the training mission, which had left all her teammates "dead". She also called out Team Blue, saying their incompetence is all that made Nova's performance look good. Tosh tried to quell the arguments, but would then privately confront Nova about her lack of teamwork. Nova brushed him off.
Tosh found himself in charge of a new teammate, Aal Cistler, whose low PI rating of 4.5 should have kept him out of the Academy. Cistler didn't treat the Academy seriously, prompting Tosh to criticize him. During several training missions, Cistler and fellow teammate Lio Travski (who was suffering from hab withdrawal symptoms) performed poorly, while Nova performed quite well by herself. Eventually, Tosh openly criticized Nova about her lack of teamwork, saying the rest of the team's poor performance wouldn't have mattered if Nova worked with them.
Tosh's lesson sunk in; for instance Terra helped a young trainee, Delta Emblock, with her reading tests. Tosh and Nova learned more about each other when Tosh accidentally reminded Nova of her past when discussing his own, causing her to suffer nightmares which Tosh "teeped" while he himself slept. The two mended fences the next morning. Nova also began cooperating with the rest of her team and eventually helped them succeed at their second attempt at the Valerian scenario.
In a sense, Nova's abilities made her Team Blue's 'ace in the hole,' at least in Tosh's mind. However, despite the teamwork, Team Blue began to fall apart, the reasons including Tosh's admiration for her turning into distracting attraction. Nova learned of Okyl's infatuation with Tosh, sparking hostility between the two women. Nova and Tosh kissed while out of the view of security cameras, but Academy policies forbade dating between students. For this reason, and that Okyl had seen the interaction, he rejected Nova's further advances to protect her. Nova felt bitter at Tosh's rejection, but the two still remained close in light of an upcoming urban melee exercise against Team Red. Tosh was downed at the hands of Obi Minaya during the simulation, but through Lio's technopathy, Team Blue came out on top.
In the aftermath of the exercise, Teams Blue and Red were combined into a single unit, Team Purple. Tosh and his fellow ghosts were to be sent to the fifth planet of the Baker's Dozen along with Preceptor Lagdamen, who would act as a trainer and observer. The Cyrus, a battlecruiser, would carry them. Commodore Georg Darabont introduced himself as a no-nonsense military man. The team was restricted to a single deck. While there, the ghosts learned various facts about the ship—the crew were regarded as cowards (for having retreated from the Battle of Tarsonis), the ship had not been refitted since that battle and was considerably undergunned and was undermanned as well. Tosh cheered everyone up with a rousing pro-Dominion speech.
As the ship entered The Baker's Dozen, Lio Travski picked up a distress call from Old Family heirs Bess and Rockham Kusinis from Shi, along with reports of the zerg being present. This convinced Darabont to head there and use the ghosts in combat, over Lagdamen's objections.
The first Dominion operation was a success. The ghosts used nukes to destroy a number of zerg hatcheries. The ghosts then rescued four Old Family heirs. However, the ghosts and marines were stranded from the Cyrus when their transport ship was destroyed while trying to pick them up, and the Cyrus headed toward a second cluster of hatcheries rather than pick them up. Despite their cloaking, the ghosts were detected by overlords, sparking a frenetic battle. Meanwhile, the Cyrus had gotten shot down.
Following the battle, Tosh reconsidered breaking up with Nova. He had done so to protect her, but only ended up hurting her. Their relationship was rekindled.
While downed, the Cyrus could be repaired through the use of Lio Travski's technopathy. However, large numbers of zerg were attacking the downed ship. The ghosts suggested Nova used her powerful psionic abilities to destroy the zerg at the second cluster of hatcheries, and Aal Cistler suggested her presence would lure the zerg away from the Cyrus. Tosh disagreed with this plan but Nova did not, so Tosh decided to accompany her.
Nova reached the hatchery cluster and began to "power up" her powers, causing the zerg to retreat toward their hatchery cluster. Tosh had to flee out of the area, but was slowed down by fighting roaches after his cloaking ran out. Nova's cloaking also ran out, putting her in trouble. Although Tosh had not actually made it to safety, he told Nova he had. Nova unleashed her power, killing the zerg, but also catching and severely injuring Tosh. She found him and used her psionic abilities in an attempt to save him. The Cyrus was repaired and picked up Tosh and Nova. The former was put into an infirmary where Lagdamen scanned his brain.
Meanwhile, Director Kevin Bick was ordered by Emperor Arcturus Mengsk to subject all the ghost trainees to a memory wipe as he wanted to keep the fate of the Old Family heirs secret. The trainees were wiped, but the injured Tosh was not subjected to the process. Instead, Lagdamen told Nova that Tosh was suffering from "delusions" from an accident. Nova saw him at the Academy's infirmary. While holding a normal conversation, they also telepathically discussed the battle of Shi. However, Nova could not remember it (or the rekindling of their relationship) and believed it was just a delusion he was having. Tosh said that everything would "be like before... as if nothing ever happened".
He reappeared as a mysterious arms dealer and pirate. He was considered so dangerous he was barred from the seedy Deadman's Port by local mercenaries. Tosh developed an intense hatred for Arcturus Mengsk and the Dominion. In 2503, ghosts began to disappear. Tosh made a reappearance during this time.
The Second Great War
"Well, I need someone to balance out your sophistication and good manners."
"The guy ain't right in the head, brother! I can appreciate some good, honest craziness. But that guy? He's got something broke inside."
By 2504, Tosh's Goons had developed a spectre-activating facility at Avernus Station, where he collected jorium and terrazine. During the Second Great War, he contracted Raynor's Raiders to pirate resources needed to produce spectres, ultimately for use against the Dominion. He believed Jim Raynor would be amenable to his anti-Dominion motives. Tosh hired the Raiders to mine minerals on Redstone III. The Raiders accepted it as a typical mining operation for profit. The spectre did not mention the minerals' jorium content, which acted as a psi-enhancing drug.  Tosh embarked upon the Hyperion afterward.
Through interactions with Raynor, the spectre expressed how much of a threat Kerrigan possessed. In Tosh's mind, she had to be wiped out before she killed them all. He could also sense that Zeratul visited Raynor. Raynor eventually confessed to what he had seen—a protoss-zerg hybrid. Tosh couldn't explain it, but hearing Raynor's words, he could sense what the future would bring. Tosh couldn't say whether the future was set in stone or whether it could be altered.
In regards to the Raiders' rescue of Agrian colonists, Tosh was suspicious of why the zerg hit the world so fast, and told Raynor that Ariel Hanson was a "honey trap". He suspected she was hiding something.
Tosh's assessments appeared to have some weight to them, as the Agrian colonists who made it to Haven began succumbing to the zerg hyper-evolutionary virus. Against Hanson's will, the Raiders put the infected down, including Hanson herself. Tosh offered some sympathy to Raynor, who had to eliminate the scientist himself. He pointed out that the situation could have been much worse if the Agrians had entered the Core Worlds and advised Raynor not to form attachments.
After the operation on Redstone, Tosh approached the Raiders to obtain terrazine from protoss altars on Bel'Shir, which were defended by the Tal'darim. The protoss attempted to seal off the altars but the Raiders made off with seven canisters of terrazine.
Matt Horner received a transmission from an unknown source, explaining Project: Shadowblade. Tosh admitted to being a spectre, but claimed the transmission came from Mengsk in an attempt to divide them. Raynor agreed to let the matter pass, but wasn't sure if he could trust Tosh. Meanwhile, UNN broadcast a report on stealth-using operatives launching an attack on Nephor II, which Tosh displayed great interest in.
- Gabriel Tosh(src)
Next on Tosh's list of objectives was to rescue some of his previously spectre allies from New Folsom Prison. However, Nova contacted Raynor and warned him against further cooperation, claiming that spectres were uncontrollably violent. Though Raynor was displeased with Tosh's secrecy, the rebel was unwilling to trust a Dominion agent. Raynor's Raiders rescued large numbers of people opposed to Arcturus Mengsk from New Folsom Prison, including some of Tosh's spectres.
Afterward, Tosh met with Raynor and Matt Horner. With the Raiders prior help, the spectre was prepared to continue the fight to destroy the Dominion. Horner was disturbed by Tosh's purely destructive motives. In turn Tosh thought Horner's idealism and the fight for freedom would ultimately be a futile one, as Mengsk's fall would only lead to the rise of another tyrannical ruler, and another one after that. Raynor concluded that he and Tosh were similar in their single-minded, and perhaps self-destructive, pursuit of Arcturus Mengsk, but believed that they were nonetheless paving the way for a better future, even if it was one that Raynor and Tosh were not meant to be a part of.
An aggrieved Tosh contacted Raynor from six light years away, and tried to torture the rebel with a voodoo doll. Unbeknownst to Tosh, the doll was attuned to Tychus Findlay instead, whose drinking in the Hyperion's cantina was rudely interrupted. Raynor was unaffected and rejected the spectre's claim that they would both do anything to win against Mengsk. Tosh was distracted enough for Nova to sneak up behind and stab him to death.
- Tosh to Raynor(src)
Tosh was grateful for Raynor's aid and agreed that only volunteers could become spectres within the Raiders and that no neural resocialization would be involved. He submitted data to engineer Rory Swann so that spectre equipment could be manufactured.
Tosh was impressed with Raynor's raid on UNN Studios. A raid on the Castanar space platform was another matter however, where a psionic "scream" from a hybrid reached him on the Hyperion. Tosh had never experienced such a thing before and hoped he never would again.
Gabriel Tosh can stun enemy units in a small area, dealing 35 damage.
Gabriel Tosh can protect himself with 300 shield points for a brief period of time.
Gabriel Tosh drains half the life of an allied unit, gaining 2 points of energy per hit point drained.
Gabriel Tosh can drop a nuke which deals 700 damage + 500 vs structures, after Raynor's Raiders gives him access to several of them.
- Tosh made an early appearance in StarCraft II story mode gameplay at BlizzCon 2008. Here, he was a member of the Raiders from the outset of the game's story. His dialogue however, in regards to the need to kill Kerrigan, remained intact and was ported into Wings of Liberty.
- Tosh might be a reference to Peter Tosh, a member of the reggae band, the Wailers. This could also be a double reference as there are two artists with similar names, Peter Tosh and Peter Gabriel. There for it could be derived from both their last names.