S.H.I.E.L.D. is a fictional espionage, special law enforcement, and counter-terrorism agency appearing in American comic books published by Marvel Comics. Created by Stan Lee and Jack Kirby in Strange Tales #135 (Aug. 1965), it often deals with paranormal and superhuman threats.
The acronym originally stood for Supreme Headquarters, International Espionage and Law-Enforcement Division. It was changed in 1991 to Strategic Hazard Intervention Espionage Logistics Directorate. Within the various films set in the Marvel Cinematic Universe, as well as multiple animated and live-action television series, the acronym stands for Strategic Homeland Intervention, Enforcement and Logistics Division.
In the 21st century, Bruce Banner joined S.H.I.E.L.D., allowing them to use the Hulk as a weapon in exchange for providing him with the means and funding to create a lasting legacy for himself (Indestructible Hulk Jan. 2013).
In the video game Marvel Super hero Squad Online, there is another version of the Hulk character called "Indestructible Hulk". The character description says that the Hulk became an agent of S.H.I.E.L.D., the character is accompanied by a small robot. The character's strongest attack is a joke with the idea of the Hulk working for this group: He prepares to attack and the robot calls in an air attack that does the job for him, and the Hulk is upset about it.