X, Y, Z is a progressive death/thrash metal project from Rosice, Czech Republic, formed in the late 1990s from the ashes of defunct band Monastery. Masterminded by multi-instrumentalist Igor Mores, who has played in bands like Hypnos and Forgotten Silence, the project blends drone, jazz, and extreme metal into experimental compositions across releases like "UnCommon Space" and "The Right Way of..."

Xang is a progressive metal project from Cambray, France, formed in 2022. The project explores complex musical structures and atmospheric soundscapes within the progressive metal genre, reflecting the depth and ambition of the French progressive music tradition.

XCIII is an avant-garde progressive metal project spearheaded by Guillaume Beringer from Nice, France, with the name referencing Roman numeral 93 and Charles Baudelaire's poetry. Their 2022 album "Void" was mastered by Steve Kitch of The Pineapple Thief, and their sound draws from influences like Ulver, Porcupine Tree, and Anathema to create dreamy, hypnotic soundscapes that blur the lines between progressive metal and post-rock.

Xemplar is a progressive metal band from Florence, Italy, formed in 2007. They craft sophisticated progressive metal compositions that draw from the rich musical heritage of their Tuscan home, delivering intricate arrangements and ambitious songwriting.

Xenomorph is a progressive death metal band from Leiden, Netherlands, formed in 2021. They craft complex and forward-thinking death metal compositions that push beyond conventional boundaries, emerging from the Netherlands' deeply rooted extreme metal underground.

Xenosis is a progressive death metal band from St. Ives, England, formed in 2015. They craft intricate, technically demanding compositions that blend progressive complexity with death metal aggression, contributing to the growing UK tech-death scene.

Xephos is a progressive/industrial metal band from Maybole, Scotland, formed in 2016. They merge the experimental ambition of progressive metal with industrial textures, creating a futuristic and atmospheric sound from the Scottish lowlands.

Xepsura is a progressive metal band from Newquay, Cornwall, England, formed in 2020. They deliver expansive and atmospheric progressive metal from England's southwestern coast, exploring ambitious musical territory with intricate arrangements.

Xerxes is a progressive metal band from Barschwil, Switzerland, formed in 2015. They craft intricate and technically demanding compositions within the progressive metal framework, drawing from the rich tradition of European progressive music.