The Sorrow

Overview

The Sorrow is the only member of the Cobra Unit that is not alive during the events of operation Snake Eater in Metal Gear Solid 3. He still appears as a boss in the game and attacks by raising the dead soldiers and bosses that the player has killed up until that point in the game. He also uses blasts of energy to hit the player as they progress through a river of spirits and during the fight shows the player all the soldiers they have killed in the game up to that point.

Backstory

The Sorrow was a well known and respected psychic and medium but also a fearsome warrior. He became renowned for his ability to converse with the dead and to channel their spirits into his body to utilize their skills. His codename is reflective of the profound sadness he found on the field of war and this is the emotion he takes into battle. He was part of the Boss's Cobra Unit formed prior to World War II and along with the unit took part in many skirmishes which helped turn the tide of the war towards an allied victory.

From the intense fires of war the Sorrow and the Boss found love for each other on the battlefield and it was here that the Boss would give birth to their child, the man who would later be known as Revolver Ocelot. This child however was immediately abducted by the Philosophers, the precursor to the Patriots.

When the Cold War began the Boss and the Sorrow found themselves on opposite sides of this political and ideological rift. In 1962 the Boss, now America's most respected soldier, met the Sorrow as enemies in Dorinovodon. The Sorrow realized that the Boss had to do her duty and finish her mission and it is highly likely that he allowed the Boss to kill him.

The Sorrow shows up several times during the Virtuous Mission and in Operation Snake Eater, usually when the Boss is nearby and bleeding from his left eye. He appears the have the ability to make it rain. At the end of Metal Gear Solid 3, after the Boss is dead, it is possible to see the ghosts of the Boss and the Sorrow appear and then fade away together. 

Trivia

•  Upon reaching the end of the river and finding The Sorrow's body during his "Boss Fight," Snake is given the "Spirit" camouflage pattern as a gift, which makes your footsteps completely silent. The fewer enemies you killed during that time, the easier is is to reach the end.