Creosote oil is a product made from coal that can be used to fuel furnaces and lamps, or creosote logs when placed in the world.
To make creosote oil, you'll need:
-1 block of coal
-1 bucket
-A furnace
Start by smelting the coal in the furnace to create Coal Coke. This will give you 1 Creosote Oil for every piece of Coal Coke that you smelt. Next, take your bucket and fill it with water from a source block. Now Right Click on the Coal Coke with the Bucket of Water to extinguish it and receive your Creosote Oil!