Grey
Snake could always slip into the dark shadows, since his uniform was pretty much one main colour; grey. It was as grey as charcoal, grey as the clouds overhead outside, and as grey as a dead corpse's skin.
The colour reminded him of war. Many artists depicted the scene with bloody reds, silver linings, and pitch-dark black, but the ones that were completely grey reminded him best of the battles he'd fought. Of course, the reds, the silvers and the blacks were there, but nothing seemed to stick out for him except for grey.
He didn't know why this was. Maybe it was because everything seemed so bleak in the midst of war; people dying, being tortured in the worst of ways, truths and betrayals made clear, the destruction of innocents...
He didn't want to think about it anymore. He didn't want to see, or hear, or feel it anymore. He didn't want to be involved in this anymore.
If he had a choice of how his life would end, it wouldn't be in a blaze of glory, dying bravely in battle.
If he had a choice of how his life would end, it would be peacefully and quietly, far from the grey bleakness of war.