Hard Techno Selections, Vol. 21 presents tracks and remixes from Erykk Mtk, Air of Wave, TC Dj, Black Ahead, Agent Zero, DS3, Regal, Franck Antenucci, LEVRE, Andy Bsk, SU 47, HANNIBAL K, Fuma Funaky, Jared Pastore, Endemic, Wrong Format, Mandidextrous & Matt Scratch, Mark Rey, Davide Di Blasi, Chris Lo, Chris Cue, Jonathan De Maio, RiVid, Verys & OKKOTO, B-Ya!, Dynamo City, Datcher, Sergio Pardo, Jordi Lazaro, Misinki, Pumio, Rik Arkitech, Ayako Mori, Moshe Galactik