Void Liquid is a super dense liquid.
You can create a small amount of it by combining toxic sludge + worm blood + fungus/fungus powder. It can also be obtained by combining all the essences and converging on the moon.
Upon creation, void liquid will quickly drill through the world because of its density, but will not destroy materials, unlike acid.
As of the Feast Update, Void Liquid can be consumed. Upon consumption, no effects will be given to the player character and your stomach will be filled by 8%.