The many multifarious iterations of the 7Form netlabel and artist collective have yielded some of the strangest and most exciting music of the last half-decade, and though it can often feel next to impossible to even find the new mutations, much less keep up with them, it’s worth it to hear one-in-a-million works of art like Anti-Mass Spectrometer. As the title and cover artwork imply, samples extracted from the Half-Life games feature prominently throughout the two lengthy “iterations,” from dialogue fragments and shuffling footsteps to blaring menu sounds, explosions, and incessant gunfire. Unlike Graham Dunning’s Panopticon, however, this music is neither spatially confined nor sonically dependent on the game’s engine; in addition to the scrabbling frenzies of screams, shattering glass, slews of bullets, and other Source-sourced effects there are constant musical invasions both harmoniously atmospheric and jarringly out of place. Though these garish plunderings often seem randomly beamed in from some other dimension, the editing work done on many of them (such as the disconcerting isolation of Taylor Swift’s vocals from “Love Story”) shows their addition is more surgical than that, which mischievously implies some hidden meaning that will evade even the most desperate pursuers to the ends of the earth. Another mystery arises in the many similarities between the tracks as well as the fact that the second iteration is exactly 1.5x the duration of the first (elements also frequently recur in slowed-down form), which suggests they’re simply the same material played at different speeds… except they aren’t. I checked! Bizarre, fascinating stuff that I won’t soon forget.