So, I think we can all agree that Spiral Knights has a pretty great soundtrack, but what about video game music from other games?
Perhaps it's memorable to you because of the moment it occurs in the story, or perhaps it just gets you pumped; is it atmospheric, or just plain relaxing? Whatever your reason, share it here! (a short explanation coupled with a link would be good)
To get the ball rolling:
http://www.youtube.com/watch?v=wp6QpMWaKpE
Bioshock - The Ocean on his Shoulders
This piece gives me shivers every time I hear it. There's a lot of emotion put into the strings, and it really gives you this sense of hopelessness.
http://www.youtube.com/watch?v=Z2GHF8icAXI
Super Mario Galaxy 2 - Final Boss
I know the word is very much overused nowadays, but this song feels epic. Perfectly matches the scope of the whole game and makes me want to get in a fight with a titan.
___
EDIT: Sorry.
Starbound - all the peaceful planet music
Of all the peaceful game music I have heard, Starbound's music is definitly the best there is. It really fits in, just peacefully roaming around a planet, I just, really don't know. It's good, ok? Good until you encounter a hostile monster who ruins it with unfitting music
Mario and Luigi: Dream Team - The Final Antasma Battle
Do I really have to explain this one? Too bad Bowser decided to steal the spot light...
Pokemon X/Y, Xerneas/Yvetal Theme
See above