Goldenflame Dragon has added a new spell to The Dark Unknown:

Today’s progress- added the Light spell, and some code edits to make the rendered light update as soon as the spell is cast. It has a sound effect, too.

Additional adjustments to how the game displays the effect of the spell are evidently still required, but even so: it’s good progress. What would an Ultima-like game be without a Light spell, after all?