The Sorrow

The Sorrow (ザ・ソロー) was the "Spirit Medium Soldier" of the Cobra Unit. Although he has no actual unique combat abilities like the other Cobras, The Sorrow is gifted with the powers of a medium. He is able to summon the dead and assume their combat abilities by bringing their spirits into himself. Communicating with dead soldiers also gives him several advantages during a battle, such as learning of enemy positions. Like the other Cobras, his codename reflects the emotion he brings to the battlefield.

Early Life and Career
The Sorrow was born sometime during the mid 1900s to early 1910s. The Sorrow and The Boss fought together as part of the Cobra Unit during World War II and participated in the Allied landing at Normandy in 1944. During D-Day, The Boss was pregnant with her and The Sorrow's child and she gave birth to their son, who was then taken from them by agents of the Philosophers. After the war, he worked for the Soviet Union. He also turned a double agent planted in the Soviet Union by The Boss over to their side and gave fake analysis of the schematics of one of the Sputnik models, although he did not know that The Boss was the one who planted the sleeper agent in the first place. After The Boss's failure in the Mercury Mission, The Sorrow and The Boss encountered each other in Tselinoyarsk, 1962. The Sorrow was ultimately killed by The Boss, at his own request, in order to ensure the safety of their son, whom the Philosophers had threatened to kill if both were to survive. Before he died, The Sorrow told her, "the spirit of the warrior will always be with you." His son would later become a Major in GRU, codenamed Ocelot.

In September 1964, during the Virtuous Mission, the surviving Cobras were reunited with The Boss, who had returned to Tselinoyarsk. The unit, under the employ of GRU Colonel Volgin, were there to capture Soviet rocket scientist Nikolai Stephanovich Sokolov, whom CIA agent Naked Snake, was attempting to extract himself. The Boss's presence attracted the attention of The Sorrow's spirit, which had remained in Tselinoyarsk since his death. His spirit accompanied the rest of the Cobras, without their knowledge, as they made off with their prize, after Snake was thrown from the Dolinovodno bridge by The Boss. The Sorrow's remains were later seen by an injured Snake, before his rescue from Tselinoyarsk, located on the riverbank on which he had washed up.

The ghost of The Sorrow appeared to Naked Snake on several occasions, during the latter's return to Tselinoyarsk in Operation Snake Eater. As he did so, he often cried blood and was accompanied by rain falling from the sky. The Sorrow observed Snake during the events of his mission, and occasionally offered helpful hints, such as a key radio frequency.

When Snake met The Sorrow in the spiritual realm, after jumping from a waterfall, he was forced to walk down a seemingly endless river, so that he would "feel the sorrow of those whose lives he ended." He made Snake face the spirits of every single person he killed during his mission. However, he did not intend for Snake to stay forever, as evidenced by his comments when Snake tried to touch The Sorrow's corpse near the end of the spiritual walk. The spirits of the fallen Cobra Unit members also appeared. The Sorrow also projected images into Snake's mind with an attack, which foreshadowed his past and his death.

He was later seen helping Snake by indicating how much time was left before the C3 explosives destroyed the Shagohod's hangar. It was also theorized that The Sorrow was responsible for summoning the lightning that killed Colonel Volgin, because he was seen shortly thereafter, floating behind EVA and smiling.

The Sorrow was last seen by Naked Snake towards the end of Operation Snake Eater, standing next to the ghost of The Boss, reunited and vanishing together.

In 2014, The Sorrow's likeness made an appearance as one of Screaming Mantis puppets. His puppet gave Screaming Mantis control over dead FROGS in the vicinity. After Screaming Mantis was defeated, her doppelganger appeared to affend Solid Snake. However, a mysterious force threw them back to the spirit realm, followed by The Sorrow appearing and saying the last words he said as a human from The Boss to Snake: "The spirit of the warrior... will always be with you."

Trivia

 * Despite "The Sorrow" being his codename, the ghost of The Sorrow was always smiling whenever Naked Snake saw him, with not one occasion where there was a frown upon his face. Similarly, The Boss/The Joy rarely smiled during the events of the Virtuous Mission and Operation Snake Eater.
 * The Sorrow, along with The Boss, are the only Cobra Unit members who did not have their microbombs activate upon death.
 * During Naked Snake's encounter with him, The Sorrow exclaimed, "You will all be killed by your sons," and, "You... no your sons, and your son's sons." He also told Naked Snake that "light and darkness" breeded within him.
 * The Sorrow made two appearances during Liquid Ocelot's Insurrection. He appeared as one of Screaming Mantis's puppets. The Sorrow Doll had the ability to control dead corpses. The second appearance was where he stood on the upper balcony smiling down at Old Snake, while saying his memorable quote.

Behind the Scenes

 * Yukitoshi Hori, The Sorrow's Japanese voice actor in Metal Gear Solid 3, also voiced Vulcan Raven in Metal Gear Solid, who was also a spirit medium and a practitioner of the supernatural.
 * It was originally implied that Revolver Ocelot had inherited a form of The Sorrow's (his father's) spirit medium powers in order to explain how Liquid Snake's spirit was able to take over his body. This explanation was later disregarded in Metal Gear Solid 4, along with all other supernatural aspects of Ocelot's possession.
 * The Sorrow's reasons for allowing The Boss to kill him (revealed in Metal Gear Solid: Peace Walker) were very similar to why Olga Gurlukovich helped Raiden during Metal Gear Solid 2.

Appearances

 * The Sorrow's skeleton can be seen during a secret R1 scene after Snake is thrown off of the Dolinovodno bridge, after Snake bandages himself. In Metal Gear Solid 3: Subsistence, if the free camera is on, the player can also see the skeleton by rotating the camera before going into the menu to cure Snake's wounds.
 * When Volgin is torturing Snake in the interrogation chamber in Metal Gear Solid 3, pressing the R1 button when the screen prompts the action causes Snake to see The Sorrow floating behind The Boss, holding up a piece of cardboard with the digits 144.75 scribbled on it. This radio frequency can later be used to open Snake's cell door when he gets sealed in the holding block. Even if the player failed to see this digit, it can be viewed in another hidden R1 scene where Snake throws food out to the guard who eventually gives in to Snake's demands. He will show Snake a photo with the same frequency on the back of it.
 * During the conversation with Volgin, The Boss, and EVA in the Shagohad's hanger The Sorrow can be seen several times behind Volgin holding a digital clock showing the time until the C3 Snake planted blows up.
 * After Volgin dies, when EVA is about to hug Snake, holding R1 will allow the player to see The Sorrow floating behind her, implying that he was the one who killed Volgin.
 * After The Boss is defeated, holding R1 and looking to the left allows the player to see both The Sorrow and The Boss's ghosts.
 * In Metal Gear Solid 4, there is a secret L1 scene after defeating Screaming Mantis and Psycho Mantis appears, and then disappears again is when The Sorrow is heard saying, "The spirit of the warrior will always be with you." The Sorrow will be seen floating on the second floor, before dissipating. To see this, the player must press L1 and look to the top left-hand side corner.

Boss Fight

 * During the encounter with The Sorrow, all radio support personnel will scream Snake's name if the player tries to contact them, similar to the Game Over screen that occurs if Snake dies. This includes Para-Medic, although the player can still save the game.
 * During The Sorrow experience, Naked Snake will obtain all of his weapons and equipment (besides camo and food) prior to his capture, although the weapons are useless during the battle, since The Sorrow nor the dead spirits can be wounded. However, after the fight, Snake will no longer have this equipment (except for the equipment he obtained after his capture) until he meets EVA behind the waterfall when she returns it to him.
 * Even if Snake drains the Cobra Unit's stamina in battle, their ghosts will still appear when Snake has his experience with The Sorrow. This is possibly due to the unit's microbombs going off even in non-lethal kills. The Cobra Unit will serve to indicate how many more waves of spirits Snake has to encounter.
 * If the player saves the game during the fight with The Sorrow, the location will be listed as "?"
 * Because of the nature of his boss fight, The Sorrow is one of only two bosses (the other being The End) where the player can get his camouflage without defeating him non-lethally in Metal Gear Solid 3. If the player makes it to the end of The Sorrow's river and uses the revival pill, when Snake gets his gear back, he will have obtained the Spirit camouflage, which allows Snake to drain stamina using the CQC choke. It will also eliminate footstep noise. In an optional codec conversation with Sigint, Snake says that it was a "gift" from The Sorrow.
 * How long the battle will last and the number of ghosts that Snake has to endure depends on how many soldiers are killed. At the absolute minimum, 4 can be faced (as the Cobra Unit member's ghosts will end up being faced regardless of whether Snake defeated them lethally or non-lethally.).
 * If the player kills soldiers without the use of a lethal weapon, such as dropping their unconscious bodies in water, at electric fences, or in quicksands, or throwing poisonous animals or food to poison and kill them, etc the soldiers will not appear during the encounter with The Sorrow.