King Sombra

King Sombra is a unicorn who appears in the third season's premiere The Crystal Empire. His name has been confirmed by show staff members.

Name and design
"Sombra" is the Spanish word for "shadow". A differently-shaded version of the armor around King Sombra's neck is used for the 2012 Design a My Little Pony Finalists poster, as part of Steel Masquerade's armor.

Pony Wedding microsite
King Sombra first appeared on Hasbro's Pony Wedding microsite, which has been accessible since July 2012, before any information about the character was released publically. The quiz does not refer to him by name. In the microsite's Wedding Quiz section, the quiz "Your dream wedding location!" includes the question "Who should be the MC?", with Sombra as the choice that steers the quiz's result to the Crystal Empire. Writer M.A. Larson wrote on Twitter regarding the quiz's image of King Sombra that was presented to him: "Interesting. I read about that in a script but never seen it before."

New York Comic Con 2012
King Sombra is mentioned by one of the Crystal Ponies and Twilight Sparkle in the promotional clip for The Crystal Empire shown at Hasbro's My Little Pony panel at the New York Comic Con 2012 and later uploaded to Hasbro's My Little Pony Facebook page. His distinct eyes briefly flash over the Crystal Pony who mentions his name.