Roar, by and far, is a great opening song, starting soft and building, without ever being too strong. Its a song about breaking free, and letting loose, doing what you feel is right, not following the crowd. Its a very relaxing song, and also shows some of Glen's amazing vocal ability/range.  Honestly, this song captured me when I first played Retrospectacle long ago.

The night's cut in half by the scream of a child
The cry of a newborn, primal and wild,
The prince of a tribe that lives on in the blood that runs through you.

In school he is taught to sit silent and dream,
At home he stares mute at a glare on a screen,
And nobody tells him that he can speak free if he wants to.

Run, little brave,
Follow the muse,
Your life is your art.
Fill up your lungs,
Sing form the heart and...

Roar, roar with the lions,
Howl, howl at the moon.

The little girl makes up a song every day,
She sings as she rises, sings as she plays,
Some things can never be taken away from the children.

Her little head translating dreams into rhyme,
Her heels fire rhythm, her fingers tap time,
Her eyes are the light and her laugh the antennae to heaven.

Learn all the rules,
Throw them away,
Your life is your art.
Take what you need,
And sing from the heart, and...

Roar, roar with the lions,
Howl, howl at the moon,
Roar, with the voice of emotion,
Howl the songs of the soul.

And the prince grew to be a king,
And he took her hand,
And God made man to sing.

Roar, with the voice of emotion,
Howl the songs of the soul.
Roar with the lions,
Howl at the moon.
Roar with the lions,
Howl.  Yeah!
Roar with the lions, with the lions, yeah,
Howl at the moon.