Template:Character infobox Dettlaff van der Eretein, also known as The Beast of Beauclair, is a character in the Blood and Wine expansion for The Witcher 3: Wild Hunt. He is a higher vampire who was responsible for regenerating Emiel Regis Rohellec Terzieff-Godefroy with his blood and nursing him back to health.
Regis was once defeated by Vilgefortz during the assault on Stygga Castle. Geralt and his companions had assumed that being reduced to a puddle of plasma was a fatal condition, but Dettlaff was able to save Regis, completely regenerating him. They became "blood-brothers," and Regis is forever indebted to Dettlaff for his selfless actions.
- It was horrifying to watch... that gentleman suddenly turned into a ghastly beast, with claws, and... tore those men to shreds with the precision of a master butcher…
- – a witness to Dettlaff's attacks
- Dettlaff is a higher vampire and one of the most terrifying creatures the world has ever known. Some vampires of his sort live among men easily and inconspicuously, sometimes even gaining the respect and admiration of their community. Yet even the most civilized vampire can be incredibly dangerous if provoked, and Dettlaff... Dettlaff was far from civilized.
- When in his two-legged form, Dettlaff strikes in surprising and unique ways, so one must be extremely alert and attentive. His razor-sharp claws, wielded with great strength and precision, are his chief weapons, yet he can also wield weapons of human devising with extraordinary skill.
- Like all higher vampires, Dettlaff can turn into fog and envelop opponents. When fighting a vampire in this form, one must watch out for magic puddles and attacks from the air. When wounded, Detlaff tends to assume his winged form, using these powerful appendages to stun his foes near effortlessly.
- One must remember higher vampires are immortal creatures and thus do not fear for their lives while fighting, meaning they take every risk. They are able to turn invisible and can regenerate strength during combat. All in all, they are supremely difficult foes, even for a witcher.
- Milton’s murderer was very swift. Even with years of witchering under his belt, Geralt could barely keep up with him. Soon, it became clear the killer was as clever as he was fast, by entering an old warehouse where he set a trap for Geralt. In this way Geralt had his first face to face encounter with the Beast of Beauclair – and discovered it was a higher vampire named Dettlaff.
- A fight immediately ensued which might have ended very badly for the witcher, had he not been saved in the nick of time by an old friend, Regis, who put a stop to their battle. After that, Dettlaff fled away in a puff of fog…
- Dettlaff van der Eretein has the surname of Marta Dettlaff, junior concept artist at CD Projekt RED.