A subgenre of death metal, which combines the brutality and power of death metal and combines it with the odd time signatures, complex song structures, and other characteristics of progressive rock and progressive metal. The subgenre can also be synonymous with technical death metal. While some progressive death metal can be just as brutal and chaotic as normal death metal, bands like Opeth sometimes have softer, sometimes acoustic guitar work reminiscent of 1970's progressive rock bands such as Gentle Giant, Yes, and Genesis. Progressive death metal bands are also sometimes influenced by jazz and classical music.