Cobra Unit
From the Metal Gear Wiki
The Cobra Unit was a legendary team of soldiers that were assembled by The Boss in 1942 to combat the Axis Powers. Together it's said that they nearly won the war single handedly. They were later disbanded in 1947, but, following The Boss' defection to the Soviet Union, were reunited in 1964 during Operation Snake Eater, where they fought The Boss's final apprentice, Naked Snake and were all ultimately wiped out by him.
The Cobras all had microbombs attached to them. When they died, the microbombs automatically detonated and they exclaimed their codename. Even if they were defeated by wearing down their stamina, the bombs would still activate. The Boss also had a microbomb, but she probably had it removed after World War 2 ended.
