Cerberus in Wikipedia
Cerberus, (pronounced /ˈsɜrb(ə)rəs/);[1] Greek form: Κέρβερος,
/ˈkerberos/[2] in Greek and Roman mythology, is a multi-headed
hound (usually three-headed)[1][3][4] which guards the gates
of Hades, to prevent those who have crossed the river Styx
from ever escaping. Cerberus featured in many works of ancient
Greek and Roman literature and in works of both ancient and
modern art and architecture, although, the depiction and
background surrounding Cerberus often differed across various
works by different authors of the era. The most notable
difference is the number of its heads: Most sources describe
or depict three heads; others show it with two or even just
one; a smaller number of sources show a variable number,
sometimes as many as 50...
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