Whoa, what? That's not just a classic, it's a staple!
Off the top of my head I can think of many epic tales that feature overpowered enemies:
Lord of The Rings
Star Wars
Erfworld Book 1 ()
Pick your favorite Cthulhu Mythos story
Matrix
Dark Crystal
Predator
Dracula
Sword of Truth
Alien
War of the Worlds
Thomas Covenant
Any Star Trek episode/move/book where they face off against the Borg
Just about every horror story ever written
I could go on, but I think my point has been made.