She portrays him as a very charismatic but extremely dangerous character. His charm is what attracts followers to his dark ideology.
In the 'Crimes of Grindelwald' novel, J.K. Rowling presents Grindelwald as a powerful and calculating wizard. He is not just a one - dimensional villain. His actions are often driven by his grand vision for the wizarding world, although his means of achieving it are clearly wrong. He is able to sway people to his side with his powerful speeches and the promise of a new order. His magic is also quite formidable, which makes him a terrifying adversary. His past with Dumbledore also haunts his character, as it is something that is both a source of his strength and weakness in some ways.
Grindelwald in the novel is depicted as a complex character. He has a vision of a wizard - led world, which he believes is for the betterment of the wizarding kind, but his methods are cruel and unethical. He is shown to be highly intelligent and manipulative, using his wits to gain power and influence. His relationship with Dumbledore also adds depth to his character as it shows a different side of him from his public persona as a dark lord.