“ If it was a castle, it was the strangest one he had ever seen.
He of course saw the main tower - taller than anything he had seen outside of Stoneholt, the spire looked fragile and was topped by a glassed-in chamber.
The outer wall was so gently sloped that it would have only stopped a horde of hobbling old men, an able-bodied soldier could stride up to its crest with little effort. Within one saw a huge, nearly perfect bowl-shaped area with the base of the tower in the centre, covered in hundreds of mirrors.
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This structure is a massive solar collector designed by the Wizard-King Aardwal in centuries past. He used the concentrated light in his investigations into the magic of light, and in the fashioning of flash crystals.”
“ A world where most people know a few cantrips and even non-magical people can help to cast spells. Which is just as well because the big spells can only be cast with the help of large numbers of people.Most large spells tend to protect borders and stop earthquakes as they can be done legally, but there are those willing to cast bad large spells s well.A major part of law enforcement in this world is preventing evil magic.”
“ The PCs traveling along the road/path/trail begin to hear a low droning sound. As they approach they find their path obstructed by hundred of thousands of droning insects. Locusts swarm though the air, feasting on the grass and plants. Passage will be slowed, but the insects pose no threat to the party, aside from being crunchy and disgusting underfoot, climbing into pouches and eating exposed food goods.”