Exobiologicals

Biologicals are produced by Outerfolk or Colossi through some physiological or mental process, rather than by a work of craft.
Vile amber and vile nacre are both produced by the living components of ilithid nautiloids. Vile amber is a waxy, protective build up of congealed ifril that coats the nautiloid's soft tissues and protects them from the influence of the World. It hardens over time and is shed as spheres of resinous vile amber, which has many uses in forbidden alchemy.
Vile nacre is the hard, brittle outer shell of the nautiloids hull. When a nautiloid dies, the nacre of its shell is reclaimed to create armoured voidsuits.
Psychonite is a pale material, with a similar consistency to vile nacre. It is created by the mental powers of the ilithids, Unlike other biological, psychonite is a short-lived substance, becoming inert on the death of either its creator or its bound user, and rapidly degenerating into a soft, toxic powder.
Dreamstone is a catchall term for the materials created in a Beholder's nightmare zone. Within the zone, this material can have any physical properties imaginable. When removed from the zone, a dreamstone object, regardless of its apparent nature, quietly collapses into a pearl-like stone of small intrinsic value and approximately one percent of the weight of the nightmare form.
Foul Ichor is a rare biological, the gold-black blood of a wounded Colossus. Since few Colossi have moved on the dome since before the Cataclysm, most pools of foul ichor have been destroyed, or harvested, but a few remain. For one with the nerve and audacity, the slumbering forms of torpid Colossi present a near-limitless supply of ichor and its transformative properties, but the risks of carelessly employing the ichor are great, and the miasm which surrounds it conducive to such carelessness.
Finally, Voidbone is the substance of the Colossal internal architecture. This structure is not precisely a skeleton, but the analogy is close enough. Voidbone is tough, strong and flexible. It makes excellent, if unnerving, bows.