Natron is a salt mixture that occurs naturally in arid environments. It's white to colourless when pure, but shades to grey or yellow when impure.
It could also be used to disinfect wounds and wash stubborn stains, like blood.
After hunting down and killing Rudjek, the nomarch of the nome and a member of the Order of the Ancients, the Medjay Bayek of Siwa was taken to Nitria by Nefertari, the chief healer of the village, when she found Bayek injured near the Bent Pyramid.
The following year, Bayek returned with the intent to thank Nefertari for helping him; Rudjek's widow still lived in the village, as did Rudjek's lover, and the villagers believed Bayek killing Rudjek had 'cursed' the village, for the nearby shrines of Anubis had been disturbed.
Around the same time, Memphis was believed to be cursed, and a foul stench haunted its streets. Bayek was asked to investigate and solve the issue, and he learned that the natron used at the mummification temple had been tainted. The Lizard, a member of the Order of the Ancients had arranged the natron used at the temple to be mixed with white Saqqara sand, threatening the temple head and his daughter. Due to this meddling, the natron failed to dry out the corpses, and the mummies rotted.
Behind the scenes