The Invasion of '83

The Invasion of '83 (83年の侵攻 83-Nen no shinkō) was an incident that occurred in the fictional world in Saitama Prefecture in the fictional Japan on Halloween of 1983. The attacks ranged from cyber wars and massacres that costed the prefecture a total of 300 lives and nearly ￥5,000,000,000 (around $50 million) in damages.

Konata was five months old when the incident happened. Her mother was killed by Dr. Manhole's Super Mecha Death Drill while trying to defend her and Soujirou from him with the Lightning Rod. In addition, Kanata's power ended up draining into Konata, which caused her to grow a large ahoge that she has.

Background
It was a normal Halloween on October 31, 1983. During that time, while the children of Saitama Prefecture were trick-or-treating, a group of Team Ankoku hackers disrupted it and made it gruesome. In addition, the attacks ranged from serial killing to cyber wars that killed more than 300 people and wounded 2,500 others.