Sooo many good endings...

Two winners for this category. First up is Beautiful Cruel World, the 1st ending of Attack on Titan.

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The graphics in this ending are beautiful, following the main female character Mikasa's backstory as she grows from a young innocent girl into a warrior through various events, all shadowed in the ending. And she's not alone. We see a glimpse of her step-brother, Eren Jaëger, who has grown alongside her, thus his transition from a kid to a soldier. They've made this journey together, and at the end, they're facing each other, ready for battle.

The lyrics, too, are beautiful, with lines like:

{Note I did a translation to fit the tune. Sorry if it's not very good}
In this beautiful, cruel world we're forced to live upon.
All I can do is to ask you why
For a reason why we're still alive? Oh-
Dedicate your hearts, but with our strength --
And our weakness --
What will we protect before we drift?
Are our efforts still worth it?
It makes no sense...

{Literal translation below, as seen in the video}
In this beautiful, cruel world
All I can do is ask why we're still alive.
Oh, with our strength -- and our weakness --
What are we going to protect if there's no sense in anything anymore?

Uso (SID) is the second one, from Fullmetal Alchemist: Brotherhood. It's the first ending of the '09 series.

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Like BCW, it recaps the life of Edward and Alphonse Elric and what has happened so far. The comic-style drawings and the transitions between scenes fit perfectly, and the major characters from the show until the second ending appears all fit into the short animation. Plus, the very end is hilarious.

The tune is calming but the actual lyrics themselves can be slightly eerie.

{English Translation by Jennifer Uzumaki}
Do you somehow remember how we gazed up at the atmosphere
And how we watched the sunset go and fade away?
As I walk to the future, I'll still keep the promise that I made
From all those endless summer days.

{Literal translation from video}
Say, do you remember the sky, the scarlet sky,
Do you remember it from that day?
We made a promise and a vow while the early summer wind circled us
And we clung close together.

(For those of you that don't know, the scarlet sky refers to a burning house.)

Honourable Mentions:
Black Butler: Book of Circus ED
Aoki Tsuku Michite - AKIRA

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Fullmetal Alchemist: Brotherhood ED 4
Shunken - SCANDAL
Credit less ending

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