There are a number of Munktiki skulls with a limited edition run of 25 for its particular color (green, pink, purple, yellow). Additionally, there are themed versions such as a multi-colored Dia De Los Muertos version, a Halloween Pumpkin version, and an open edition with a traditional ivory colored skull with brown detailing around the teeth and eye sockets. This version is the "Black Metal" edition in black and white with corpse-like "make-up" around eye sockets and mouths. Black metal is an extreme subgenre of heavy metal music. Common traits include fast tempos, a shrieking vocal style, heavily distorted guitars played with tremolo picking, raw (lo-fi) recording, unconventional song structures, and an emphasis on atmosphere. Artists often appear in corpse paint and adopt pseudonyms. During the 1980s, several thrash metal and death metal bands formed a prototype for black metal. This so-called first wave included bands such as Venom, Bathory, Mercyful Fate, Hellhammer and Celtic Frost. A second wave arose in the early 1990s, spearheaded by Norwegian bands such as Mayhem, Darkthrone, Burzum, Immortal, Emperor, Satyricon and Gorgoroth. The early Norwegian black metal scene developed the style of their forebears into a distinct genre. Norwegian-inspired black metal scenes emerged throughout Europe and North America, although some other scenes developed their own styles independently. Some prominent Swedish bands spawned during this second wave, such as Marduk, Nifelheim and Dark Funeral.