INVSN (formerly Invasionen and before that The Lost Patrol Band) is the music project of Swedish Punk rock musician Dennis Lyxzén. In contrast to his other projects, Refused and The (International) Noise Conspiracy, this started out as a solo career and much more folkish and softer than his prior music endeavors. The band was previously called the Lost Patrol Band; however, the name was changed because the American group, The Lost Patrol holds the North American trademark on the name. As the name changed, the band started to write music in Swedish.

In 1999, Lyxzén put together a release titled "Songs in the Key of Resistance" which was written in the political vein that Lyxzén's fans best know him for. The album received mixed reactions. Critics often blasted the album for straying from its creator's punk roots, while others were impressed by Lyxzén's ability to diversify his musical output.