A folding knife with a blade constructed from shape-memory alloy that returns to its factory-set geometry after being deformed by impact, bending, or deliberate reshaping. The Recall's blade can be bent 90 degrees, twisted, or even partially flattened, and within seconds it will flow back to its original razor-edged profile. The weapon cannot be permanently damaged by any force short of melting it.

The MS-6's shape-memory blade is activated by body heat — the alloy's transition temperature is set at 32 degrees Celsius, meaning the blade begins self-correcting the moment it is held in a warm hand. When cold, the blade is malleable enough to be bent and hidden in configurations that do not resemble a weapon — folded flat against a belt buckle, coiled inside a bracelet housing, or compressed into a cylinder that looks like a pen. Once warmed by body contact, it unfolds and rigidizes into a fighting knife within four seconds.

Crucible developed the Recall as a concealment weapon for operatives who face thorough physical searches. The blade's ability to be deformed into non-weapon shapes defeats visual inspection and manual pat-downs. Standard weapon scanners detect its metallic signature, but the shape presented to the scanner does not match weapon profiles in detection databases, often resulting in the blade being classified as a harmless personal item.