Goshal was the leader of the Fire Nation Intelligence Department which was a specialized agency that monitored the actions of Fire Nation citizens, media outlets, and military units. The Intel Department also dealt with high profile political and military prisoners. The Department specialized in dealing with matters of treason, interrogations, terrorism, and corruption. The Intelligence department had system where staisfactory military units had red scores. Any unit that had questionable actions was placed in the yellow category and was monitored more closely. Each year, a unit could be taken off the yellow list and moved to the red list.
Green units, were at the worst tier of the compliance list. Members of green units were immediately captured, imprisoned, or executed for their disobedience. The Intel Director had a rank that was over that of the Fire Nation Generals and Admirals. Although Goshal wasn't known for publicly giving orders and didn't attend military meetings; he had the ability to check General and Admirals to make sure they were following Ozai's ordiances. Goshal had no greater ambition than to be Ozai's most trusted officer.
Abilities
Goshal was a gifted firebender. He was a top ten bender during the last year of the Hundred Year War. Goshal had experience that made him a deadly firebender and he had a ruthless mindset that made him a difficult opponent for anyone. Goshal had a gifted mind, but he wasn't a genius like Azula or Macai. Goshal's intelligence was also hampered by his arrogance which still was less than Zhao and Ozai's staggering conceit. Goshal was moderately insecure, which made him likely to lash out against potential opponents or people who may have undermined his authority.
Goshal was known for having flames with a dark organe exterior (like Kanna's). The dark orange exterior flames were more explosive than most flames but were also a bit less hot than most orange flames. Goshal's inner flames were bright yellow, making them hotter than most yellow core flames. Ultimately, Goshal's flames had the same heat level as most flames but they were more explosive. The biggest difference between Goshal and Kanna's flames was that Kanna's flames were a bit larger than Goshal's and Goshal's were a bit hotter than Kanna's (who's flames were a bit less hot than average).
Goshal was capable of jet propulsion but he used a more limited form of the ability than what the likes of Ozai, Kett, Asad, Eyre, and Macai were capable of. Some top benders like Ozai could stay in air for a long time while propelling themselves with fire. Goshal could only launch himself across the battlefield with his flames. He had advanced shoes that could take the impact of an abrupt landing of from up to thrity feet in the air without taking damage. Goshal used the same jet propulsion ability and shoes as the Intel Troopers who served under him.
Goshal was the most powerful of the Intel Troopers, which was an elite unit of master firebenders. All of the Intel Troopers and officers never fought together. Sometimes Goshal would fight with one officer or his assistant Captain Pion. However, the Intel Department wouldn't risk sending more than two top-level Intel officers into battle together. Even an Intel Captain was said to have authority equal to a General. Goshal fought in an underground tournament with other intel officers where he defeated the other competitiors in order to secure his command position. All of the competitors were drilled by Ozai to ensure they were mentally and ideologically fit for to lead the department.
Goshal was literally one of the best of the best within the Fire Nation. Despite his abilities, he wasn't known like Azula, Zuko, or Macai. Goshal's lack of notoriety was due to the nature of his position. Although Goshal was less known by the general Fire Nation public and members of other nations; Goshal was well-known by the top leaders within the nation. Goshal had studied Azula, Macai, Iroh, and Zuko's fighting styles. He knew their strengths and their weaknesses in case he ever needed to fight them. Goshal also studied Ozai secretly, although such an action was formally forbidden.

Director Goshal was known for flames which had a dark orange exterior (slightly less hot than normal) but a bright yellow interior (slightly hotter than most fire).
Personality
Goshal was incredibly loyal to the Ozai's Fire Nation regime. He was put in command of the Intelligence Department after the last leader was kicked off of office due to his previous loyalty to Azulon. Ozai believed it would be best to find a new leader who more closely followed his own ideals. Goshal proved to be even more brutal than his prodecessor, but also a bit more reckless. There were two occassions where Goshal had nearly compromised the Intel Department for being too brutal and not negotiating enough however the department covered its tracks by getting its hands even ditier and through more bloodshed.
Goshal despised Macai the moment he became a captain in the 31st Company. He believed Macai was spoiled and only got his position due to his family name. Goshal had a minor royal title that was enough for him to gain his position, but he still had to work to gain it. Goshal worked with patience, dedication, and his wits. However, Goshal also used blackmail, corruption, intimidation, and manipulation to gain his position. Goshal didn't particularly like Eyre, but he had some respect for the General due to his competence and unyielding loyal toward his nation.
Goshal thought Zhao was incompetent but was careful in his interactions with him because of Ozai's friendship with him. Goshal believed Azula was a cunning young woman who deserved her position but also believed she showed signs of instability. Goshal believed she would utlimately fail at some point and he thought Zuko was pathetic. Despite his low viewing of Zuko, Goshal believed Zuko would eventually become a ruthless leader and surpass Azula (though he did not publicly share this view). Goshal couldn't help but somewhat dislike Azula, seeing her as a spoiled brat like Macai. Still, Goshal respected Azula more than Macai for her ability to accomplish difficult tasks on her own without much guidance.
Goshal noticed that much of Macai's great achievements were done with the guidance of mentors like Eyre, Hazo, and Kenshin. Goshal believed Macai would choke and fold under pressure the minute he had to handle things on his own. What Goshal didn't realize was Macai had loyal friends who would have his back even if the mentors weren't around. The more that Macai fought on missions, the stronger his bond grew with his allies. This made Macai special.
So many leaders like Goshal paid little attention to their men's concerns and put themselves first. They were too focused on their own ambitions and their nation raised them to be like that. Macai was trained to use others for his benefit, but the young Commander couldn't help but care about those who served alongside him. What others saw as a weakness, Macai saw as a strength. This strength would utlimately serve Macai well in his darkest hours and teach Goshal an important lesson by the end of the Hundred Year War. Goshal was a man of logic and not faith. Goshal believed everything could be done by might and not compassion. Goshal's values had gotten him far enough to be at the top of the Fire Nation but it ultimately wasn't enough to keep his nation from coming crashing down.