Beginning in 2013, the band released a string of critically acclaimed albums which were all crowd-funded by the band's fans, known collectively as the Legion of Thunder. Time's Arrow (2013), The Lesser Key of Solomon (2014), Tales from the Deadside (2015), and Who Do You Think We Are? (2016) each found a bigger audience than the previous album, growing the band's fanbase worldwide. Tales from the Deadside was a collaboration with comic book publisher Valiant Entertainment, based on the Shadowman comic series.
In 2018 A Sound of Thunder will release it's seventh album, It Was Metal, accompanied by an original graphic novel and animated video. The advance single "Els Segadors (The Reapers)" has already gone viral in Catalonia reaching the EU200 mainstream music chart.