Comet

When using the Spyglass (or a telescope) in Ultima V, a comet seen in the night sky over any planet of the Britannian Solar System meant that the city with the virtue the planet was named after, was under attack from one of the Shadowlords.

With the destruction of all three Shadowlords, these comets vanished as well.

Now, with the threat of the Guardian looming over Britannia, the comets have begun again...