The Darkened Knight

It's failing my memory
Of the epic story
Where the protagonist is a darkened knight
That rose from the ground
And 'till his end shall fight
At his horse galloping sound

I saw him killing and run
At the moonlight and below the sun
Galloping to the east
Seeking for the beast

And he camped on a cave
Thinking about the people he have to save
At sunrise sword on his hand
Galloping through the arid land

After a long journey he found the beast
Duelled it with sword and fist
Killed it without caring about the corpse he left behind
That one day someone shall find...