Effects: When imbibed this mutagenic potion provides access to a special enhancement of the Intelligence attribute; this upgrade augments the intensity of a witchers' Signs, but only during moonrises.

Preparation: The potion is made by mixing a golem's obsidian heart with ingredients providing one measure each of vitriol, quebrith, hydragenum and aether; a strong, top-quality alcohol must be used as a base.

Duration: Instantaneous

Toxicity: None

Golems are usually described as unthinking constructs and have effectively become synonymous with insentience. Yet only the most powerful mages know how much effort is required to cast a spell on a golem's stone heart, to force the creature to follow even the simplest commands. Renegade mages somehow learned to draw on the complex magic contained in a golem's obsidian heart to produce a powerful, mutagenic potion that affects witchers' brains.