The Red Viper Makes His Way to 'Game of Thrones'

Season 3's Red Wedding left a lot of room in the cast for new additions, and showrunners David Benioff and Dan Weiss have already announced one of those additions: bad boy Oberyn Martell, aka the Red Viper.

[Related: 'Game of Thrones' Red Wedding Reaction: Twitter Explodes, the Actors Sound Off]

Like the wonderfully devious Tyrells (Margaery and the Queen of Thorns, Lady Olenna), the Martells hail from the southern kingdom of Dorne. Unlike the Tyrells, Oberyn Martell is headed to King's Landing to avenge the death of his sister.

Warning: The following contains mild spoilers ...

Oberyn's sister was murdered by the Mountain That Rides, Gregor Clegane (big brother of the Hound), during the rebellion that put Robert Baratheon on the throne. Though much smaller than Clegane, he's called the Red Viper for a reason (hint: It starts with a "p" and rhymes with "shmoison"). Remember the Hound's flaming swordfight with Beric in Season 3? Look forward to that times 10 when Oberyn and Gregor clash. Expect it to get doubly gruesome if they get into the things that the Mountain did during the rebellion (hint: "shmurdering shmabies").

Of course, Gregor Clegane is not the only member of the royal court who should be wary of poison...

[Related: The Westeros Burn Book: 14 Epic 'Game of Thrones' Insults]

Benioff and Weiss cast Pedro Pascal, whose profile has risen in the past few years with recurring roles on "The Good Wife," "Red Widow," and "Graceland."

"The Red Viper is sexy and charming, yet believably dangerous; intensely likable, yet driven by hate," Benioff and Weiss share. "The boys love him, the girls love him, and he loves them all back." Alluring and dangerous — easy to see why he's a favorite of fans of the books.

If you'd like to get a taste of the Viper before "Game" comes back in 2014, Pascal will also be in Season 3 of "Homeland," which premieres this September on Showtime.

[Related: All the Burning Questions We Have for Next Season of 'Game of Thrones']

This is probably the only major casting announcement of the next season. Expect to see a lot of returning faces, though some more unexpected than others...

Another tantalizing glimpse of red: The Red Woman herself, Carice van Houten, has Instagrammed a page of her script for Episode 1 of Season 4. Though nobody dies yet, this is just the cover, so it's probably safe to assume that your favorite character is dead by page 2.

Check out what the "GoT" cast on the red carpet: