I don't know if these count, but these are two original songs that directly reference Castlevania in their lyrics (original compositions made by pro bands, not fan-made remixes/arrangements by game-tribute bands like Megadriver). There might be more.
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Vampire Killer by heavy/power band
Battleroar from their
Age of Chaos CD (2005)band info:
http://www.metal-archives.com/bands/Battleroar/5121The face of a vampire
That grins in the black
It waits,
In the castle cold
The wings of a demon
That glides in the air
He looks out for blood, so beware
Run, run for your life
Flee from the black pits of hell
Fight, fires alight
Warlocks are casting deadly spells
Strange is the land where spirits dwell
Race against the sands of time
He's got you in his coil
The leather wings and talon's rage
Unfolding to destroy
No mercy for the victim
Who treads upon the blade
And falls apart
Sorcerers and witches
Fear the cracking of your whip
Revenants and skeletons
You'll show them all your tricks
Your weapons are a legend
The chain of holy steel
And sacred shield
Hear the voice from the past
You will find out at last
There's a quest that is waiting for you and your soul
A swirl of the chain, the darkness, the rain
The fury, the pain and your power that soars
Vampire Killer
The scream of a virgin
That bleeds in the dark
Resounds
In the dungeons cold
The laugh of a demon
That glides in the air
His life is your blood, so beware
Force, moonlight's the source
Fueling the strength of your foes
Strike, strongest in might
Free now the village from this curse
Hunting the undead overlord
Centuries have passed by
And still the evil reigns
Stealing blood from cursed nights
We all know who's to blame
The hunger of the vampire
The mesmerizing eyes
And killing bite
Sneaking as a night-thief
Through the ancient corridors
Your flying whip, a charming snake
It's ready for some more
The vengeance of the hunter
A fighter who was trained
To lift the curse
Hear the voice from the past
You will find out at last
There's a quest that is waiting for you and your soul
A swirl of the chain, the darkness, the rain
The fury, the pain and your power that soars
Vampire Killer
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Symphony of the Night by American heavy/speed band
Skelator from the
Death to All Nations CD (2010)band info:
http://www.metal-archives.com/bands/Skelator/5092Screams break the silence
Dreams turn to nightmares
Flee from the forest
Oh, the battles begun and the dawn will not come
What a terrible night for a curseThe undead are walking the earth
Through the black of the night all his children take flight
Spreading the pain of rebirth
Pain now consumes me
Hatred's inside me
Fate has destroyed me
I must save my land from the hand of the damned
And vanquish this horrible curse
The undead have conquered the earth
Through the black of the night all his children take flight
Spreading the pain of rebirth
His form is completed, he cannot be beaten
By even the mightiest of warriors
The bodies are mounting, the darkness corrupting
The king of the night has returned
Now the battle's been won and Simon lives on
Liberating his land from the curse
The undead are banished from earth
Now the sun will arise and light up the sky
The morning had vanquished the night (lyrics in bold almost directly reference some text from Simon's Quest!)