Lost Generals

The Lost generals are a group of generals fired by Garmadon. After being fired they started a collony inside the jungle. They built a village with a volcano on the middle so one day they would be able to take revenge.

History
When Lord Garmadon was unsatisfied with his generals, he used to fire them. From a volcano. However he didn't know that his generals were creating a small colony into the woods.

While the Ninja and Garmadon were searching for the ultimate ultimate weapon in the jungle, the Lost Generals attacked them. Their attack was succesful as they captured Lloyd and Garmadon. The other Ninja escaped and came back after watching a bunch of kung-fu movies in order to train themselves. However, the Lost Generals were going to throw Lloyd and Garmadon in a volcano. The Ninja sneaked undercover and resqued Lloyd and Garmadon but one general ripped off Lloyd's arm. The Ninja found his arm and escaped by building a vehicle.

Ninjago.com Description
''Before Garmadon’s current General #1, there were a whole lot of other leaders of the Shark Army. All of them disappointed Garmardon in one way or the other, and wound up being launched from the volcano into the jungle. Now they are waiting there, singed and seething, waiting for a chance at revenge on Garmadon.''