It is said about... Hydra

"Hydra the nine-headed water serpent, off-spring of Typhoon and chidna, lived deep down in the swamp and killed with the poison-like breath.
As one head was cut off by enemies, two new heads re-appeared.
It was Hercules to kill Hydra by burning her neck after decapitate each head and trapping her body under a huge rock, where it's still buried until this day."

In the middle of the swamp I'm safe for every stranger,
No one ever dares to cross the line.
Take good care be aware my head senses danger.
Eighteen eyes will notice every sign.

Right before their eyes,
They will see the beast arise.
Nine heads, she's the creature of the sea,
Watch her crawling through the night,
No one will save you.
How long can I reign this kind of fear,
Will someone overthrow my fight,
Where is my saviour?

For every head that you attack I'll raise two up before you.
Better leave your weapons by your own.
Just one man, one fearless man,
who sees his vision come true,
He fought with fire - buried her under stone.

Right before their eyes.
They will see the beast arise.
Nine heads, she's the creature of the sea.
Watch her crawling through the night.
No one will save you.
How long can I reign this kind of fear.
Will someone overthrow my fight.
Where is my saviour?