I am Sylvanas Windrunner, Queen of the Forsaken. And if you will not serve me in this life, then you will do so in the next.
Lich King, Algalon and Spine of Deathwing.
It's a shame, because Spine holds my #1 spot of most unsatisfying and poorly made boss ever created, too. But nobody can deny the visual of riding on the back of Deathwing was pretty awesome and if they'd made the boss fight more exciting and fun it would have felt pretty intense.