Since the event with disney making the EU non cannon now. There is only one cannon mission for the delta squad. I will be talking about the cannon. Plz visit here for the legends adventures from the game http://starwars.wikia.com/wiki/Delta_Squad (warning spoilers for Republic Commando)

Delta Squad was an elite clone commando squad that carried out missions for the Grand Army of the Republic during the Clone Wars.

"There were no survivors on Devaron. Everyone was killed, including Master Halsey and his Padawan."

―Boss, reporting on the events on Devaron

During the Clone Wars, the commandos of Delta Squad were dispatched to Devaron in the aftermath of the battle waged there and recovered the bodies of Jedi Master Halsey and his Padawan, Knox, and returned them to Coruscant. Upon landing at the Jedi Temple, the squad was met by Jedi Council Masters Obi-Wan Kenobi, Plo Koon, Adi Gallia and Saesee Tiin, who concluded that the deaths of the Roonan Jedi and his apprentice were a sign of a new threat to the Republic. Their suspicion was confirmed when security footage of the massacre was recovered including a hologram of Halsey's death at the hands of an as-yet unknown assassin.

TCW mini logo Star Wars: The Clone Wars – "Witches of the Mist" (First and only cannon appearance)

http://starwars.wikia.com/wiki/Delta_Squad/Canon

MEMBERS in order as the papercrafts

RC-1138 "Boss"

"Alone against all these droids...heh, they don't stand a chance." ―Boss

RC-1138, known by the nickname of "Boss", was Delta Squad's leader. Holding the rank of sergeant, Boss had earned both the respect and loyalty of his squad, and in return he did his all to be a strong and effective leader. Relatively taciturn, Boss was not a man of many words, and much of what he did say came in the form of orders issued to the other members of Delta Squad. Interestingly enough, despite being raised and trained by Cuy'val Dar sergeant Walon Vau, Boss would come to speak with Jango Fett's own Concord Dawn accent and speech patterns—though this trait was common to the flash-learned standard clone troops, as well. Boss cared a great deal for his squad, and like most other clone commandos, viewed his squadmates as brothers.

RC-1140 "Fixer"

"Sir, you realize this is against recommended protocols." ―Fixer

RC-1140, or "Fixer" to his comrades, was the acknowledged second-in-command of Delta Squad, and was a soldier who believed in doing his job by the book. Fixer was the squad's expert in all things technological, and was justly the squad's go-to man for slicing and code-breaking. Gruff in his demeanor, and a serious no-nonsense type of person, Fixer had a habit of calling his squadmates by their numerical designations rather than their chosen nicknames. Fixer often took it upon himself to curtail the playful teasing of his squadmates Sev and Scorch while in the field, though he would occasionally engage in the verbal sparring during down time.

RC-1207 "Sev"

"In order to achieve maximum combat efficiency, some guys say they need to get in the zone. Sir, I live in the zone." ―Sev

Blue Glass Arrow Main article: RC-1207 RC-1207, who drew upon his designation's final digit to don the nickname "Sev", was Delta Squad's most skilled sniper and perhaps its fiercest fighter. Sev enjoyed combat, and decorated his commando armor with blood-red markings[10] that not everyone could tell whether it was paint or real blood.[2] Sev possessed a grim sense of humor and a powerful drive to succeed, believing that any failure of his would be letting his training sergeant, Walon Vau, down and disappointing him. Though he deeply respected and revered Vau, Sev also felt a sense of jealously toward the commandos who had been trained by Kal Skirata, who treated his trainees as though they were his sons. A common joke among the rest of Delta Squad was that Sev was a bit of a psychopath, even teasing that his cloning tank had been spiked during gestation. Sev kept a count of every Geonosian that he killed during the course of the Clone Wars, intending to reach a goal of 4,982—the number of clone commandos killed during the Battle of Geonosis, for which Sev intended to take revenge.

RC-1262 "Scorch"

"Can't keep a good clone down, sir." ―Scorch

RC-1262 acquired the nickname of "Scorch" following an ordnance accident that left him and his training sergeant, Walon Vau, without eyebrows for a brief period of time. A competent soldier, Scorch served as Delta Squad's explosive technician, performing demolition and rapid entry duties for the squad on a number of missions, a job which he thoroughly enjoys. Aside from his talents with explosive ordnance, Scorch possessed an overdeveloped sense of irony and found his place in the squad as their resident wisecracker, able to find humor in almost any situation. Scorch spends much of his time verbally sparring with fellow squad member Sev, playfully maintaining a brotherly relationship of back-and-forth teasing and friendly rivalry.