Beyond the Sky and To Far Away Times are my favorite ending themes in video games...both by Yasunori Mitsuda. Dude knows how to evoke the feels that's for sure.

Edit: Also the ending theme for Dragon Quest II, VIII and Smiles and Tears from Earthbound. 

My favorite RPG. Always sad but fulfilled that it reaches its end with such an amazing tune backing it up.

N o c t u r n e  b a b y !

Across the many Merio games, 64 and Color Splash have the greatest credits tunes.

From Zelda, Skyward Sword and Wind Waker. Also reminds me that the only flaw of Breath of the Wild is that it doesn't have an actual credits theme.

@Super_Boom

Really short, but holy shit the impact when you finish the first chapter of Deltarune.

Just Xeno X.

Stair Fax Zero, I love 64's but I prefer the added main theme of Zero's for the first credits theme.

This frigging medley, all my feels.

As much as I don't really care about Graces F's OST or the game in general, it does end on a great note with the ending theme.

The end medley of every vocal track in Styling Star is just soooo good, a wholesome end to a wholesome game.

Das enough for now.

Ico - You were there

It is a perfect fit for the game, for the ending, for the haunting atmosphere in the castle and for the strange sence of freedom present in the end.

Twi I didn't want to cry tonight DXDXDX

I agree with a lot of the choices I've already seen, but gonna add the two below that I beat recently and are still on my mind. 

I mentioned this one in the other thread, but boy was it a punch to the gut to play this song after the event prior the credits. Seeing all these moments in Rex and Pyra/Mythra's relationship was just so powerful, and they lyrics were so fitting it might as well have been her singing to him. Absolute amazing ending song to an amazing game.

Same as above, really fitting song to a great game. The Japanese version is touching as well, but hearing it English feels more natural to the setting IMO.

Instinctively I think of three games (well one is kind of more than that)

I can't wait to hear Jammin' Sam Miller's restoration of these two DK themes. Any fan of the SNES DKC music should look him up and his efforts to restore the trilogy's music to what might've been intended before SNES compression.

I like the entire ending theme for FFVIII and most other FF games but the part I'm looking for is the piece called "Final Fantasy" it features in most of the games but my favourite rendition (and Nobuo Uematsu's too coincidentally) is in the credits of Final Fantasy VIII.

Special mention for Kirby's Adventure, it's the next one that came to mind.

I seen this was already on here, but don't think it can be iterated enough just how great this soundtrack really is, being for whatever reason when the game released people were saying the soundtrack was bad..... Not even close to the reality of things. Easily my favorite ending track for the Xeno series, and one of my favorite tracks in gaming period.