Fate/Grand Order: First Order is a special animated film adaptation of mobile RPG game Fate/Grand Order based on popular Fate/stay Night visual novel and franchise.
On this story, there is a secret organization called Chaldea which held a purpose of preventing extinction of the human race via the usage of time-travel. An unexpected turn of events then caused the protagonist Ritsuka Fujimaru alongside his demi-servant Mashu Kyrielight a.k.a Shielder, and the organization's director transported back to 2004 to investigate and remove the abnormality in the area known as Fuyuki City, which is caused by the tainted Holy Grail War outcome.
The group encountered the now-corrupted servant Lancer ( true name: Medusa ) in one of the city's vicinity, which is full of stone statues that scattered throughout the area.
Lancer immediately confirmed that the statues are formerly human, which now turned into stone by her abilities and stated her intention to add the group into her collection. Disappointingly, there aren't any transformation scene for those statues and Lancer is later defeated.
Interestingly, it seems that the petrification effect is a stone shell that covered the victim's body as seen in one scene where a statue has its head decapitated by Lancer followed by blood gushing from the now severed body. Although curiously, no blood ever comes from shattered statues during the next battle scene, which possibly suggested further stage of the petrification.
The petrifications also seems to be permanent, as there is no signs of the victims reverting after Lancer's defeat.