From the Scrolls of Gilgamesh…
The Fifth King  commands, and we obey,
that it be recorded what the sages say;
for that which the flood has lost
we forget at terrible cost;
the gods turn strange, and ever grim
the listening stars have now turned dim.
Acheron , that mighty land,
Acheron, the iron hand,
sleeps, and let it not awake.
Forever let its power break!
The Lord of Serpents on his throne
ruled the night, and ruled alone.
The Lord of Wealth, in his vaults
many and dark were his faults
dwells forever now below
never to see Anu’s glow
Where once his mountain tower rose
now the deadly Charybdis forever flows
For it is as the gods command
never the same will be the land
never again will be unfurled
the banner that once ruled the world
the evil of its unkilled king 
has lost forever its dark sting.
Not even the wisest of sages knows
Where the river of forgetfulness flows 
The Styx, still found, has wandered west 
and carries kings still to their deathly rest
Merciful the gods who brought the flood
and washed away a sea of blood.
Three thousand times, the moon’s shined bright
since Tiamat ceased her heavenly flight
Three hundred years since the second birth
Have mortals fought to reclaim the Earth
Let the poets and the spirits sing,
of Uruk, the land, and of Gilgamesh, king!
But let us remember, forget it not
that our prosperity was dearly bought
Good is our king, and wise his laws
but at the foundation, the Serpent gnaws
Let it never be that men will say,
‘Here again, rises Acheron today.’
 Traditionally, Gilgamesh was the fifth king to rule Uruk after the great flood.
 In Greek mythology, Acheron was the “river of woe,” which circled the underworld, and was sometimes used to refer to the underworld itself. However, the Scrolls of Gilgamesh seem to treat Acheron as a terrestrial kingdom somewhere in what is now northern Africa, or possibly near the Persian Gulf.
 The meaning of this passage is vague at best. Some have read it to mean that the evil king of Acheron was not killed in the war … others have taken it to mean something similar to the modern “undead.” This, combined with the references to him ruling the night, have led to speculation that this dark king was a vampire.
 Referred to in Greek mythology as “Lethe,” the river of forgetfulness was the only drinkable water in the underworld, which made the spirits of the dead gradually forget their former lives.
 Again, a river of the underworld, specifically the one that Charon carried the spirits of the dead across to enter the underworld. What “Styx has wandered west” could mean, is anyone’s guess.
(Originally posted to my LiveJournal.)