Kraang never know when to quit do they? Every single one of them angered the turtles with their annoying dialogue. One weird night, Leo had taken his brothers out on patrol when Donnie's Kraang Communicator went off, alerting them that the bots were going to heist another lab. During the battle however, Leo had noticed one specific Kraang had stolen a white glowing liquid. Determined to stop it, Leo ran after it, but the Kraang acted quickly and threw it onto Leo's body. Over the next few weeks, Leo wasn't himself.