Solemn Ending Theme

"This is my cheesy song for an RPG

Artistically invalid, but it rhymes sufficiently

And now it modulates to D

because it is the saddest of keys

To denote the tragic romance

That ended so predictably

"Cheesy RPG Song", ending theme of Turn Based Battle"

An emotional, solemn, usually slow-paced song played during the credits. Common especially in anime and video games.

The most common type is a pensive, retrospective or sad Anime Theme Song, but it can be an instrumental tune as well. Often so melodramatic that it falls into Narm territory.

Might be accompanied by a Credits Montage.

Tropes and styles commonly found in a Solemn Ending Theme:
 * Japanese Pop Music
 * One-Woman Wail
 * Ethereal Choir
 * Playing the Heart Strings

Since except in some cases the soundtrack usually supports the temper of the ending, this is often a sign of a bittersweet or Downer Ending, except in anime, where the opening theme is usually more exciting in order to build excitement for the coming show while the closing theme is more somber to provide a resting period or moment of reflection between shows.

Preferably provide links to the song (Youtube or otherwise) when adding examples. Take care, linked credits videos might obviously contain ending spoilers; to prevent this, it would be optimal to link the song without the credits video or mark credits videos as such.

Anime

 * Wolf's Rain, "Gravity". Sung in English by Maaya Sakamoto. (non-spoileriffic credits video)
 * Cowboy Bebop has "The Real Folk Blues" as the answer to the intro theme "TANK!". The series as a whole also has "Blue".
 * Outlaw Star features this for the first 13 episodes, and a slightly less solemn one for the rest of the series. Yes, both far more somber than the opening theme.
 * Baccano, "Calling". Extremely noticeable in contrast to the jazzy upbeat opening, "Guns & Roses".
 * The 3rd season of Sailor Moon featured this in the original Japanese, it was changed to an instrumental version of the US opening credit song when it ran in syndication on Cartoon Network.
 * Gasaraki features one.
 * Neon Genesis Evangelion features Frank Sinatra's "Fly Me to the Moon" sang by several different female vocalists, each with her own unique voice style.
 * Excel Saga ends with a parody of this, where Menchi laments her role as the emergency food source, while a woman translates her howls. The last episode parodies the parody with Menchi and the translator's roles reversed.
 * The ending theme of Queen Millennia. True, the title theme isn't exactly Hard Rock either, but the ending seems to be a bit more solemn.
 * More pronounced in the film version where the ending theme (different from the TV series) is sung by Dara Sadaka.
 * Future War 198X: "Pathetic Love is My Destiny" by Kazuko Kawashima. Only in the original Japanese version. The Macekered dubs replace it with a song by Asia.
 * In comparison to the more Hot-Blooded opening theme and first and third endings, "Tsubasa Aru Mono," the second ending song from Saint Beast: Kouin Jojishi Tenshi Tan, is very subdued and gentle.
 * Berserk has "Waiting So Long", a song that manages to be both endearingly Engrish-y and genuinely haunting.
 * Gunslinger Girl has another foreign-language ending theme, this time in Italian: the bleak, operatic "Dopo il Sogno".
 * Higurashi's first ending Why or Why Not. It even comes with a Next Episode preview that FITS with the end of the song!
 * Rainbow Nisha Rokubou no Shichinin has "A Far Off Distance" by Galneryus.
 * A Little Snow Fairy Sugar has "Snow Flower".

Film

 * "May It Be" for the first Lord of the Rings movie.
 * And while "May It Be" can sound hopeful and hymnlike, "Gollum's Song" in the second film is downright funereal.
 * Completing the hat trick, we have "Into the West" played over the "real" end credits of the third film.

Live Action TV

 * Gerry Anderson's UFO has a fast upbeat opening theme, but closes with an ominous atmospheric piece.
 * Game of Thrones.
 * Parodied by the Mystery Science Theater 3000 Love Theme that plays over the show's closing credits, which is a much slower, ponderous version of the theme sung over the opening credits.
 * "Now it's time to say goodbye to all our company..."
 * Kamen Rider Black: "Long Long Ago 20th Century"
 * Friday episodes of Mister Rogers' Neighborhood from 1971-72 closed with the solemn-sounding "Weekend Song".
 * A part of this song would also serve as the coda to the closing version of "It's Such A Good Feeling" used since 1972, but the solemn effect was less pronounced because the preceding portion was upbeat, and the tempo picked up again for the instrumental as Mister Rogers said his closing words.

Professional Wrestling

 * When Mick Foley first appeared as "Mankind" in the WWF, he had two themes, an entrance theme and a different, more solemn exit theme that played when he won a match.

Video Games

 * Last Scenario ends with "Moji no dengon" by Sound Horizon.
 * "Drift" by Laura Shigihara at the end of Quintessence. [credits video, non-spoiler]
 * Iji ends with a cover of the VNV Nation song "Further".
 * Many Final Fantasy games end with one of these.
 * "Eyes on me" for Final Fantasy VIII. [ending video, non-spoiler]
 * "Melodies of Life" for Final Fantasy IX.
 * Castlevania: Symphony of the Night has "I am the Wind".
 * Inverted for the dog ending of Silent Hill 2. The starting theme is melancholy, then the game ends with an upbeat J-pop anthem followed by a cheery "singing dog". The normal endings are played straight, however.
 * Also inverted in the UFO ending of Silent Hill 3 with a children's song parody and amusing cinematics.
 * Shadow of the Colossus has a very sad "Battle over" theme. It's appropriate considering that during the game you are basically.
 * Metal Gear Solid features a Gaelic one. Almost all the Metal Gear ending songs are like this, with the exception of "Can't Say Goodbye To Yesterday" and the one to the original Metal Gear (which was ridiculously peppy). "Way To Fall" by Starsailor in Metal Gear Solid 3 Snake Eater is a mournful alt-rock ballad, "The Best Is Yet To Come" is a Gaelic ballad and "Calling To The Night", "Here's To You" and to a slightly lesser extent "Heaven's Divide" are all super-melodramatic Power Ballads.
 * "Late Goodbye" by Poets of the Fall in Max Payne 2 The Fall of Max Payne.
 * Turn Based Battle parodies this with "Cheesy RPG Song."
 * Wild Arms series:
 * Wild Arms 2 has "Atomic Arms" and "Zephyr's", the ending themes of Disc 1 and 2 respectively.
 * A partial example: Wild Arms 3 has a fairly sad theme that plays whenever you quit the game. The credit theme is a softer, more solemn theme of the opening theme, though possibly not solemn enough to qualify for this trope.
 * Legend of Legaia uses this trope. See for yourself..
 * "Small of Two Pieces", the Narm Charm-loaded Power Ballad that caps off Xenogears, might not be solemn enough to qualify for this trope, but the "Myth remix" likely is.
 * Tetris Attack/Panel De Pon, a game with a very upbeat soundtrack, ends on "A Walk on a Rainbow".
 * Chrono Cross ends with the exquisite ballad "Radical Dreamers ~ The Jewel Unstolen".
 * Radiant Historia ends with -HISTORIA-, with its mellow instrumentals and retrospective, vague, sad lyrics (spoiler, but won't make much sense for anyone who hasn't played the game).
 * Mega Man Zero 4's Freesia.
 * Dark Souls has the Nameless Song., a haunting, beautiful One-Woman Wail.

Web Original

 * Sad Panda's 'Flight of Fantasy' at the end of Suburban Knights.