We don't often cover Nickelodeon's incredible 'The Legend of Korra' series in spite of our love for it, though the latest guest voices announced in advance of next week's Comic-Con 2013 panel are too good not to share. Joining the 'Avatar: The Last Airbender' sequel series are 'Parks and Recreation' star Aubrey Plaza, along with James Remar ('Dexter') and Lisa Edelstein ('House'), along with a number of others for Book 2: "Spirits."

Entertainment Weekly first reported the news, clarifying that Plaza will play Korra's Waterbending cousin Eska, whose twin brother Desna will be voiced by 'Joan of Arcadia‘ star Aaron Himelstein. Remar will lend his voice to the role of Tonraq, Korra's powerful Waterbending father, while recently-announced 'Castle' star Edelstein will play Kya, the sweet-yet-impatient sister to Tenzin (J.K. Simmons).

While Nickelodeon has yet to issue an official premiere date, also joining the cast for season (book) 2 is 'Arrested Development' star John Michael Higgins as Varrick, an eccentric capitalist and self-proclaimed “Biz-Bender,” along with 'Sons of Anarchy' star Adrian LaTourelle as Korra’s uncle Unalaq, Chief of both the Northern and Southern Water Tribes, who seeks assistance from his Avatar niece.

EW also included two photos from 'The Legend of Korra' season 2, showing off Aubrey Plaza's character Eska and her twin brother, while the second features Korra's father Tonraq (Remar) speaking at a public forum.

We'll learn more from 'The Legend of Korra' season 2's upcoming 14-episode run at Comic-Con 2013, but in the meantime check out the images below, and tell us what you want to see from Book 2: "Spirits" in the comments!

Nickelodeon / EW
Nickelodeon / EW