Heroes Next Door (The Battle of London)

The Battle of London was the event where Earth's mightiest heroes pitted against the Irken Empire.

Prelude
The conflict began when the Irken Empire enacted a massive galaxy wide conquest on other systems. However, pockets of resistance have surfaced and one of those resistance delivered a severed blow on their Armada. To counter their losses, the Irkens created robots that resembled them known as the Cluster.

The Irken overly relied on the Cluster and the robots were tasked with many of the Irken daily activities. Suddenly, one of the Cluster revolted and rallied her kind to fight back. The Irken easily trampled the Cluster's revolt until several of the Cluster created a biological weapon and had secretly installed them into their ships. Slowly, the Irken began to die out and the Cluster fled to space. To save themselves, the Irkens used their resources to download their kinds' minds and memories into PAKs, a backpack device that stores information and installed them into biological shells. It had succeed but over time, the Irken became deranged and biological shells started to deteriorate until the Irken became shadows of their former selves. The only thing that remained the same was the memory of the Cluster and they violently swore vengeance on the robots.

During their hunt, the Irken got word of a Cluster invasion on a backwater planet called Earth. They sent out advance parties to look into this and confirmed the rumors but also discovered potential within Earth's populace.