The Clash Royale hack is one of the many hacks that the SC8HcR team has developed over the years. Maybe it's the experience that gave them expertise in this matter, or it's the knowledge and professionalism. We don't know. However, we certainly know that their hack is one of the best (if not the best) hack for our beloved game Clash Royale.
You can visit their site for a comprehensive guide for the game as well as the main reason everyone is going there, the free gems.