Following Monday's addition of German electronic act Kraftwerk, Roskilde Festival announced four new acts yesterday.

Toronto alternative electronic band Crystal Castles, Iceland’s Of Monsters and Men, Colorado folk rock band the Lumineers, and Danish pop star Marie Key were the newest names added to the Roskilde poster.

The Roskilde faithful reacted positively to the announcements on Facebook, praising organisers for their picks. Sadly for Marie Key, however, fans seemed somewhat underwhelmed with her inclusion.

The news of the Crystal Castles booking attracted particular praise, as the Canadian band's third album Crystal Castles III, has continued to build on the band's buzz among critics. Fans, however, may be eager to see whether Crystal Castles’ live performances have improved, after they have been criticised for not living up to the standard of their recorded music.

Marie Key and Of Monsters and Men will be the latest Nordic bands added to the Festival’s line-up. While Marie Key will be well known to Danes given her commercially successful solo career, Of Monsters and Men are hardly strangers either. They performed a well-received October concert at Store Vega, and their debut album, My Head Is an Animal, was among The Copenhagen Post's picks for the best albums of 2012.

The Lumineers will be keen to bring their growing US popularity to Europe. Their hit single 'Ho Hey' reached third place on the Billboard Hot 100 Chart in December 2012.

You can see the full list of bands which will be playing at the Roskilde Festival here.