Add Magical Powering of Lights - With an Item

we have lamps, torches, and so on.

How about getting an item through crafting or a difficult boss fight:

You get a kind of "flame rod" and you have to stick it into the ground.

Within the range of xY blocks, the flame now shines and goes into the ground and supplies the roots in the ground with the flame.

it is a kind of energy source for larger lamps, torches, and other items that would fit with it. so that you can illuminate a larger area, especially if you are building underground. maybe a stove that runs on a flame?

perhaps this flame needs magical particles at intervals to continue supplying the roots (power lines).

Or it makes the soil more fertile by banishing the dark from the soil.

Or instead of placing lamps that illuminate an extended area, flame plants could grow out of the ground through the flame rod and illuminate a small area. i.e. glowing plants that may also remove a small part of the shroud if you want to build in the shroud.