Radiolaria

Radiolaria, nicknamed "Vex milk", are microscopic silica-based organisms forming the biological component of Vex constructs. Suspended in a luminescent, conductive non-Newtonian fluid on Vex-transformed planets like Nessus, they let it store kinetic energy. Clovis Bray I reportedly discovered that exposing them to a paracausal force produced Alkahest, and contact with the fluid can convert organic matter into Vex; the Titan Kabr was assimilated this way. See also Machine World.