"Adventure Time" is an American animated television series created by Pendleton Ward for Cartoon Network.
 The series 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 and grow and shrink at will.
 Finn and Jake live in the post-apocalyptic Land of Ooo.
 Throughout the series, they interact with the show's other main characters: Princess Bubblegum (voiced by Hynden Walch), the sovereign of the Candy Kingdom; the Ice King (voiced by Tom Kenny), a demented but largely misunderstood ice wizard; Marceline the Vampire Queen (voiced by Olivia Olson), a thousand-year-old vampire and rock music enthusiast; Lumpy Space Princess (voiced by Ward), a melodramatic and immature princess made out of "irradiated stardust"; BMO (voiced by Niki Yang), a sentient video game console-shaped robot that lives with Finn and Jake; and Flame Princess (voiced by Jessica DiCicco), a flame elemental and ruler of the Fire Kingdom.
 The pilot first aired in 2007, and it was later re-aired on the incubator series "Random!
 Cartoons" on Nicktoons Network.
 The pilot eventually leaked onto the internet and became a cult hit on YouTube.
 After Nickelodeon declined to turn the short into a full-fledged show, Cartoon Network purchased the rights, and "Adventure Time" launched as a series on April 5, 2010.
Out of Jimmy's Head (abbreviated as OOJH), is an American live-action/animated television series.
 It was advertised as the first Cartoon Network series in this genre, even though "Big Bag" was what took credit, while also including some animated segments.
 Based on the first live-action/animated original channel movie "Re-Animated", that was aired on December 8, 2006, it is produced by Cartoon Network Studios and Brookwell McNamara Entertainment (the latter known for shows such as "Even Stevens" and "That's So Raven").
 It was created by Tim McKeon and Adam Pava, who were originally the writers for "Foster's Home for Imaginary Friends" and "The Life and Times of Juniper Lee", but also the creators of "Weighty Decisions" short on Cartoon Network's "Sunday Pants" anthology series.
Cartoon Network refers to two digital children's TV channels broadcasting animated programs: Cartoon Network MENA, which serves the Middle East and North Africa region (excluding Israel, Iran and Turkey) along with Cyprus; and Cartoon Network Africa (formerly known as Cartoon Network HQ), which serves Sub-Saharan Africa.
 Cartoon Network was created by Turner Broadcasting System, a unit of Time Warner.
 Cartoon Network UK/Europe (the direct precursor to Cartoon Network feeds in the EMEA region, including Cartoon Network HQ) was launched on September 17, 1993.
 In October 1999, Cartoon Network UK became a separate feed from Cartoon Network HQ, but initially had a nearly identical schedule to Cartoon Network HQ until the latter became completely independent from the UK feed in 2001.
Boulder Media Limited (also known as Boulder Media) is an Irish animation studio.
 Boulder Media is best known for producing select episodes of the "Foster's Home for Imaginary Friends" series for Cartoon Network.
 Another project, "The Amazing World of Gumball", was produced by Boulder and Cartoon Network Development Studio Europe for the show's first season.
 They also produced the animation for season 2 of "Wander Over Yonder".
 They also animate the 2015 series of "Danger Mouse".
The eighth and final season of the American animated comedy television series "Regular Show", created by J. G. Quintel, originally aired on Cartoon Network in the United States.
 Quintel originally created the series' pilot using characters from his comedy shorts for the cancelled anthology series "The Cartoonstitute".
 He developed "Regular Show" from his own experiences in college, while several of its main characters originated from his animated shorts "The Naïve Man from Lolliland" and "2 in the AM PM".
 He himself voice acts one of the main characters in the show, "Mordecai", a blue jay.
 It was announced on July 7, 2015 and began airing on September 26, 2016 to January 16, 2017 on Cartoon Network in the United States.
James Garland "J. G." Quintel (born September 13, 1982) is an American animator, television writer, producer, voice actor, and director.
 He is best known as the creator of the Cartoon Network series "Regular Show", in which he also voiced the characters Mordecai and High Five Ghost, and the forthcoming TBS series "Close Enough".
 He was formerly the creative director for "The Marvelous Misadventures of Flapjack", an animated series that aired on Cartoon Network from June 2008 to August 2010, and a writer and storyboard artist on "Camp Lazlo" from 2006–2008.
Pencil Mania is a 1932 animated cartoon in the Van Beuren Studios Tom and Jerry series that breaks the fourth wall of theatre and film.
 The two main characters become animators in the film, and draw various cartoon scenarios against the blank background, and interact with them.
 The short was created by John Foster and Vernon Stallings (credited as Geo.
 Stallings), with synchronization by Gene Rodemich, released through Library Films.
 The opening credits are played over the song "I'm Looking Over a Four Leaf Clover".
 Run time is 6:54.
 It is believed to be in the public domain.
Foster's Home for Imaginary Friends (commonly abbreviated as Foster's) is an American animated television series created by Craig McCracken for Cartoon Network Studios.
 The series, set in a world in which imaginary friends coexist with humans, centers on an 8-year-old boy, Mac, who is pressured by his mother to abandon his imaginary friend, Bloo.
 After Mac discovers an orphanage dedicated to housing abandoned imaginary friends, Bloo moves into the home and is kept from adoption so long as Mac visits him daily.
 The episodes revolve around Mac and Bloo as they interact with other imaginary friends and house staff and live out their day-to-day adventures, often getting caught up in various predicaments.
Right Now Kapow is an American animated sketch comedy television series produced by Warner Bros.
 Animation for Disney XD.
 It is the first collaboration between Warner Bros.
 Animation and Disney.
 The series premiered on September 19, 2016 and ended on May 31, 2017.
 The series was created by Justin Becker and Marly Halpern-Graser, who previously worked on the Cartoon Network series "Mad".
 Becker also worked on Adult Swim infomercials, and Halpern-Graser also worked on Cartoon Network's "DC Nation".
 The series follows Dog, Candy, Ice Cream, Diamond, Plant, and Moon going on new adventures everyday...and find themselves in mischief.
 Every episode of the series has 3 main parts in every 11-minute segment and other random shorts.
 The series has a style of humor similar to Cartoon Network's previous series, "Mad".
The seventh season of the American animated comedy television series "Regular Show", created by J. G. Quintel, originally aired on Cartoon Network in the United States.
 Quintel originally created the series' pilot using characters from his comedy shorts for the cancelled anthology series "The Cartoonstitute".
 He developed "Regular Show" from his own experiences in college, while several of its main characters originated from his animated shorts "The Naïve Man from Lolliland" and "2 in the AM PM".
 He himself voices one of the main characters in the show, "Mordecai", a blue jay.
 The series was renewed for a seventh season at the 2014 San Diego Comic-Con International on July 25, 2014.
 The previous season contained 31 episodes in order to accommodate for the and this season will contain the normal 40 episodes from the previous seasons.
 However, it was technically 39 episodes because the last episode of the season was used for the five shorts which were broadcast on Cartoon Network in March and April 2016.
 Therefore, the five shorts took up one production code for the 40 episodes.

Question: Who are the two main characters of the animated Cartoon Network series that Boulder Media is best known for?
Answer: Mac and Bloo