Blackout

A natural phenomena with unknown causes in The World of Band. It dims all natural or Humane-made lights to near useless. There is no warning or predictions on when they'll start, and covers the entire known world at the same time.
Frale's Effects are rendered completely useless and powerless.
Beasts of all kinds, tamed, pets or livestock grow restless, and if the blackout persists longer than a few minutes start to get aggressive and eventually destructive.
The real danger of course is the Ancestral Species, who can sense the light fading and will start to crowd cities and Bridge Stonehouse to terrorize and hunt the people inside.

"The blackout only last a moment. We are lucky this time, the Department is working hard to eradicate them entirely!" -Hopeful Commonform

There is no known light that can withstand the blackout, and happens a few times a month, stopping all business, construction, and normal life and forces the citizens to seek shelter for the dangerous world they live in.

"Did you hear about the Towerway the other day? They had nothing, not even a dim candle during the blackout with all those monsters circling their tower. It's a miracle only two people were taken..." -Optimistic Highform

Those traveling through the Bridgeways are rendered near helpless out on the bridge, as the ancestor species are brave enough to climb the columns and and Towerways. Having the wrong species can destroy the protective barriers between them and the people instead can be a catastrophe for those hiding inside.