Night Owl Potion

This widens whatever light you already have and lifts the darkness at the edge of it, so a single torch reaches much further than usual. Drink one in a sealed cave with nothing lit and it does exactly nothing, which catches people out the first time. Bring a light and this makes it a good light.

Both herbs that go into it are among the easiest in the game to grow, and a couple of planter boxes at your base will keep you supplied without ever going looking. There is no reason to ration these, so brew a stack before any long caving trip.

The best pairing is a Shine Potion. Light yourself up, then see the result across a large part of the screen. That combination beats hauling a Shadow Orb or any other follower light around, and it costs nothing to maintain.

It gives the same vision the Night Vision Helmet does, so drinking one while wearing the helmet is wasted.