A core goal was to remain true to the original while making adjustments in line with the more advanced hardware.

Japan Studio's Gavin Moore, best known for his work on Puppeteer, served as the creative director for the project. Japan Studio, who assisted with the development of the original game, also assisted Bluepoint Games for the remake. After Miyazaki and FromSoftware, the development studio of the original game, gave their approval, Bluepoint Games began development of a remake following completion of its 2018 remake of Shadow of the Colossus. In 2016, Hidetaka Miyazaki, the director of the original Demon's Souls, acknowledged the demand for developing a remake but said that because the intellectual property (IP) belonged to Sony, the inception of such a project would depend on their desire to do so. The character creation feature has also been updated, with more options for customization. Although the Souls series is notorious for its difficulty, Bluepoint stated that the remake would not introduce different difficulty levels. Filters from the photo mode can also be used during gameplay, including a 'classic mode' filter intended to evoke the look of the original PlayStation 3 game. The game also includes a photo mode, whereupon using it the game will pause, something not possible in the original.

One new feature, called 'Fractured World', is a mirror mode which reverses the layout of environments.

For example, in the original game, healing grasses have no weight, so players could potentially carry hundreds of them in the remake, these healing items now have a weight associated with them so that the amount players can carry is significantly lessened, and more potent grasses weigh more than less effective ones. As with the original, players are limited in how much they can carry before their character becomes encumbered, although some aspects of this encumbrance system have been adjusted. The game features new weapons, armor, rings and items called 'Grains' which give players a temporary resistance to effects like poison, fire, and bleeding.

The Vanguard Demon, one of the game's bosses

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