Mental As Anything are an Australian new wave/pop-rock band that formed in Sydney in 1976.
 Its most popular line-up (which lasted from 1977-1999) was Martin Plaza (birth name Martin Murphy) on vocals and guitar; Reg Mombassa (birth name Chris O'Doherty) on lead guitar and vocals; his brother Peter "Yoga Dog" O'Doherty on bass guitar and vocals; Wayne de Lisle (birth name David Twohill) on drums; and Andrew "Greedy" Smith on vocals, keyboards and harmonica.
 Their original hit songs were generated by Mombassa, O'Doherty, Plaza and Smith, either individually or collectively; they also hit the Australian charts with covers of songs by Roy Orbison, Elvis Presley and Chuck Berry.
Jasmine Ying Thompson (born 8 November 2000) is an English singer and YouTube celebrity.
 Thompson began her career at the age of ten by filming herself singing and uploading the videos to YouTube.
 In 2014, she was featured on German deep house producer Robin Schulz's song "Sun Goes Down".
 This song charted within the top 10 in multiple countries including Australia, Germany, Austria and Switzerland.
 As of August 2017, her YouTube channel has over 2.8 million subscribers and over 460 million views.
Margaret Lillian Adams (born August 9, 1986), better known by her stage name Magibon, is an American Internet personality and YouTube celebrity on the video-sharing website YouTube.
"#REHASH" is the ninth episode in the eighteenth season of the American animated television series "South Park".
 The 256th overall episode, it was written and directed by series co-creator and co-star Trey Parker.
 The episode premiered on Comedy Central in the United States on December 3, 2014.
 The episode is part one of the two-part season finale.
 The episode lampoons the popularity of Internet Let's Play celebrities and the phenomena of Internet trending topics that lack actual relevance.
 The episode also references and intertwined multiple elements from previous episodes in the eighteenth season of "South Park".
 YouTube celebrity PewDiePie plays himself in this episode.
Kevin Wu () (born June 12, 1990) is an American blogger, activist and humanitarian.
 He was best known for being an early YouTube celebrity, comedian, and actor known by his YouTube username of KevJumba.
 The "San Francisco Chronicle"<nowiki>'</nowiki>s Jeff Yang has noted that Wu is not a comedian in the conventional sense but that by "just talking [he] is, well, pretty hilarious" due to his deadpan vocal delivery, animated facial expressions and tendency toward unexpected digressions.
 Wu previously appeared on The CW Television Network's short-lived "Online Nation" and co-starred with Jessica Lee Rose and Philip DeFranco in "Hooking Up" from HBOLabs (the online arm of HBO) in 2008.
 In 2010, Wu and his father, Michael, competed as a team on the 17th season of "The Amazing Race", placing seventh out of eleven teams.
 In 2014, Wu starred in crime drama film "Revenge of the Green Dragons" (executive produced by Martin Scorsese).
 In 2013, Wu ceased production of YouTube content.
 In 2017, Wu returned to social media and YouTube as a small time blogger, having emerged from a self-imposed spiritual retreat.
 Wu has since embraced East Asian and South Asian religions, a long-time interest.
Esmée Denters (born 28 September 1988) is a Dutch singer and YouTube celebrity.
 Having started promoting herself as a musician on the video-sharing website in 2006, she covered songs by many artists including Justin Timberlake and Natasha Bedingfield.
 By mid 2008, at age 19, she became one of the first music artists to exceed 100 million views on YouTube.
 At the time that was more than 50 Cent's (91 million views) or Michael Jackson's (74 million views) YouTube channels.
 Only Britney Spears had more all-time total views: 181 million.
 Denters was then signed by Timberlake as the first artist to his label Tennman Records.
 In May 2009, she released her debut studio album, "Outta Here", and toured the United States with Timberlake.
 After the label dropped her, Denters moved to London, where she competed in BBC One's "The Voice UK".
Felix Arvid Ulf Kjellberg ( ; ] ; born 24 October 1989), better known by his online pseudonym PewDiePie ( ), is a Swedish web-based comedian and video producer.
 He is known for his Let's Play commentaries and vlogs on YouTube.
Anna Sentina (born September 16, 1994) is an American musician, multi-instrumentalist, best known for her work as a session bass guitarist, live performer and YouTube celebrity.
 She has performed around the U.S. at venues such as the world famous Whisky A Go Go, the Viper Room, the Mint, SOMA San Diego, the Hard Rock Cafe and the House of Blues.
 In 2012, Sentina started a YouTube music channel that as of October 2015 has over 21 million views.
Alex Williamson (also known by his YouTube username Shooter Williamson) is an Australian YouTube celebrity, comedian, and actor.
 He became a state finalist in the 2009 Raw Comedy Award competition and is known for his solo comedy performance "Alex Williamson and Friends".
 He is also known for his YouTube comedy videos, many of which he plays the persona of "The Loosest Aussie Bloke", displaying negative bogan stereotypes for comedic value.
"#HappyHolograms" is the tenth and final episode in the eighteenth season of the American animated television series "South Park".
 The 257th episode overall, it was written and directed by series co-creator and co-star Trey Parker.
 The episode premiered on Comedy Central in the United States on December 10 2014.
 It is the second part of the two-part season finale which began with the previous episode, "#REHASH".
 The episode makes multiple references to earlier episodes over the season, as well as to previous seasons, while mainly lampooning the trend of culture constantly making trending topics with no actual relevance.
 It also lampoons news events such as the death of Eric Garner, the shooting of Michael Brown, the sexual assault allegations against Bill Cosby, and the use of celebrity holograms.
 YouTube celebrity PewDiePie appeared as himself, continuing his story line from the previous episode.

Question: What is the birth name of the YouTube celebrity who played himself in the #REHASH episode of South Park?
Answer: Felix Arvid Ulf Kjellberg