So during Khamsin's final quick time event, when you are cutting Khamsin's mech into pieces the vocals come in:
Heat of the desert
Dust settles on my face
Without a compass
The soldier knows no disgrace
Out of the ashes
The eagle rises still
Freedom is calling
To all men who bend their will
And I'd say that that's a really heroic-sounding theme about a soldier spreading freedom to those who can't achieve it themselves. But when Khamsin's two robotic arms have been chopped up, and his mech falls to the ground, broken, he is now prone and vulnerable to attacks, he shows his true colors, exclaiming "No! No, I can't lose!" and the lyrics now change to:
Here I am
Dirty and faceless
Waiting to heed your instruction
On my own
Invisible warrior
I am a wind of destruction
I love the fact that just as Khamsin shows his true colors, as a dumb, pathetic, coward, the song also represents that by changing the lyrics from a "Heroic soldier fighting for freedom" to "A mindless drone fighting because it was his order."