The new protagonist is Moccamori (모카모리), the current queen of Ürphea, standing in for her father—who is known as the Devil. She seeks to resurrect him and conquer the other continents.
A teaser image featuring two or three new characters was revealed on the Witch Spring official Naver community early August 2018 before being replaced shortly afterwards. The Games page on Kiwi Walks' website was also updated to feature a placeholder image listing Witch Spring 4 with a 2019 release date.
On August 31, 2018, the new protagonist Moccamori's concept art was revealed, illustrated by series developer Suyoung Jang. On Naver, he stated "her outfit should give you an idea of what her weapon will be."
On October 6, the Japanese iOS App Store featured the Witch Spring series and released two teaser images of Moccamori, one with the full art featured in the teaser banners, and one of her in-game appearance. It also briefly mentioned that Moccamori is the queen of Ürphea who is gathering certain materials in order to resurrect her father and control the world. Later that month, the main page on Kiwi Walks' website was updated to feature her art, and the game page was updated to add chibi art of her.
In Jang's New Years post on January 1, 2019, he announced that a new promotional video for Witch Spring 4 would be released the following week. The video was posted on January 12th.
On February 1, 2019, a recruitment call for character illustrators was added to the company's official website. A little over a month later, the banner was taken down. On March 24, 2019, a recruitment call for a 3D artist was posted.