Which episode of "Rick and Morty"  aired unannounced on April 1, 2017 and was replayed every half hour from 8pm to 12am ET, as part of Adult Swim's annual April Fools' prank?
The Rickshank Rickdemption "The Rickshank Rickdemption" is the first episode in the third season of the American animated television sitcom "Rick and Morty", and the twenty-second episode overall in the series. It was written by Mike McMahan and directed by Juan Meza-Leon. The season three premiere first aired unannounced on Adult Swim in the United States on April 1, 2017 when it was watched by 676,000 American households. On the first day of its original broadcast, "The Rickshank Rickdemption" was replayed every half hour from 8pm to 12am ET with improved ratings, as a part of Adult Swim's annual April Fools' Day joke.
Elements (miniseries) Elements is an American animated miniseries based on the show "Adventure Time" by Pendleton Ward. It aired as part of the show's ninth season on Cartoon Network from April 24 to April 27, 2017. "Adventure Time" follows the adventures of Finn (voiced by Jeremy Shada), a human boy, and his best friend and adoptive brother Jake (voiced by John DiMaggio), a dog with magical powers to change shape, grow and shrink at will. In this limited event series, which itself follows the events of the "Islands" miniseries, Finn, Jake, and BMO return home to discover that Ooo has been turned into a veritable dystopia thanks to extreme elemental magic. Finn and Jake team up with Ice King (voiced by Tom Kenny), Betty (voiced by Felicia Day), and Lumpy Space Princess (voiced by Ward) to set things straight.