Riggs and the other main cast members of The Walking Dead won the 2012 Satellite Award for Best Cast in a Television Series. For his performance in the series as Carl, Riggs was nominated for the Saturn Award for Best Performance by a Younger Actor in a Television Series five consecutive times and won the award three times in 2014, 2016, and 2018. In 2014, Riggs also won a Young Artist Award for Best Performance in a TV Series - Leading Young Actor after previously being nominated for the award in 2012 and 2013. Along with several of his co-stars, Riggs lent his voice to a special episode of Robot Chicken titled "The Robot Chicken Walking Dead Special: Look Who’s Walking" in 2017, reprising his role as Carl.
Riggs appeared in the Blumhouse Productions supernatural thriller film Mercy in 2014 and the Voltage Pictures horror film Keep Watching in 2017. In 2017, Riggs started DJing various events around the United States and released his first song "Hold Up" under his stage name "Eclipse" in December of that year. That same month, he was cast in the crime thriller film Inherit the Viper. He played the role of Cooper in the film, which premiered in 2019. He also starred in the science fiction thriller film Only in 2019. In January 2019, Riggs was cast as PJ for a multi-episode arc on the ABC freshman drama series A Million Little Things. Riggs, whose character's full name was revealed to be Patrick Nelson, returned for the series' second season.