Demonic Disturbance

Demonic Disturbance was a city-wide invasion on the capital of the Re-Estize Kingdom by an army of demons led by Jaldabaoth. Unbeknownst to the kingdom and the rest of the New World, the attack was actually orchestrated by Nazarick as part of Operation Gehenna.

Background
A small war had taken place within the kingdom, between the Re-Estize Royal Family led by Princess Renner and the criminal organization, Eight Fingers. The princess's aim was to save her kingdom by expunging Eight Fingers who had been responsible for most of the country's major crimes. To accomplish this, Renner had brought in like-minded individuals to her cause and hired Adventurers, such as the Adamantite-ranked Adventurers, Blue Roses. The two forces were seemingly locked in a stalemate until the forces consisting of Jaldabaoth and his army of demons were involved in it.

During a meeting with all the adventurers gathered for this new threat, Renner explains that the northeast corner of Re-Estize is surrounded by a wall of fire, thirty meters in height by what is known as [Flames of Gehenna]. She reasons that the flames should pose no harm to them physically except that when they enter through the wall of fire, they will be confronted by the likes of Jaldabaoth and other demonic forces.

Aftermath
The forces had managed to repel the demon invasion but it still suffered quite a large amount of losses, thousands of people were either killed or captured by the demons, a large section of the warehouse district suffered damages. The damage and losses were so severe that they caused the delay of the yearly war with the empire by several months in order to try to recuperate from the losses.