Can't kill what's already dead

Intimidate me?
No use, you can't harm me
I have returned for everyone to see
No time for empty threats
Know the new me
Unleash your fear, your hate
Unhurt I will be

Surrounded I am
But lay down your arms and save your hate
Immaterial being
I'm no one you incarcerate
I'm forever free
Unbound by the realm of flesh

You can't kill me
Can't kill what's already dead
I died long ago
Last ship that was passing by
Vanished where the sea meets the sky

You chose not to hear my screams
Turned away, escaped into your dreams
My hands tried to get a grip
To the very end
Saved my last breath for a downward trip

Sank into the ocean
Was chained to the bottom with moral
All my limbs were putrefied
My body's dead, my wraith's alive

So I'm back to intervene
Claim revenge
Blood is to be seen

Nothing to lose
No pain, no infliction
No fear reigns inside my head
You can't kill what's already dead