 He returned to the series in 2015, portraying Lao Tzu in the Season 4 episode "Eastern Philosophers vs. Western Philosophers".KRNFX also collaborated on Walk off the Earth's cover of Taylor Swift's "I Knew You Were Trouble" in 2013 and on the same band's cover of Adele's "Hello" in 2016 .In November 2016, KSTYLE TV uploaded the first video of KRNFX's collaborative beatboxing series, Betbaks, and released a cover of Korean girl group Black Pink's "Whistle" with singer-songwriter Megan Lee.