Operation Impending Doom, (sometimes called Operation Impending Doom I) was the first plan for universal Irken conquest, devised by Tallest Red and Purple (or even possibly the Control Brains). However, the plan was quickly abandoned, as Zim, newly appointed as an Invader, began destroying Irk in an enormous robotic assault walker. He was unaware that he wasn't destroying his "assigned" planet, but his homeworld (despite the fact that Irkens working the mech tried to tell him) instead. Operation Impending Doom was first covered in The Nightmare Begins, and if the episode had been longer, it would have shown the robot shooting lasers while break-dancing. It is said that all the previous Irken Invaders were killed by Zim during this rampage.