Complex sentence: While still active, Vader later developed a death metal sound with occult themed lyrics, Imperator's style of music is disputed; reformed twice in the 1990s, the band eventually dissolved in 2000, with only one studio album release.
Split into simpler sentences: While still active, Vader later developed a death metal sound with occultism themed lyrics, Imperator's style of music is disputed. Reformed twice in the 1990s, the band eventually dissolved in 2000, with only one studio album release.