Potion of slowness(1:30) is used to decrease the speed by 15 percent and also contracts FOV.
To make a potion of slowness (1:30) you need to make a potion of swiftness and fermented spider eye first. After that, you will need to use the Brewing stand to make a splash potion of slowness(1:30).
Potion of Slowness(1:30) Using Brewing Stand
After making required items, you will be able to make a potion of slowness(1:30) using a brewing stand. Go towards the brewing stand to use it. Put fermented spider eye and potion of swiftness on fire to get a potion of slowness(1:30). Add this potion in “ready to use” stock.
You can see the potion of slowness(1:30) in the image below. After successfully making a potion of slowness, you can use this potion anytime you want.