Dracorage Mythal

The Dracorage Mythal is an ancient mythal, or elven ritual, created during the Time of Dragons. The original intent of the mythal was to repel dragons, but instead flare ups of the mythal cause all dragons in the vicinity to grow more agitated and violent until they become little more than mindless beasts.
Though halted, the Dracorage Mythal was never completely dispelled, and every couple of centuries flares up again. The last time the Dracorage Mythal flared up was in 1373.