 There were many times that Shredder could have just left Krang at the mercy of the Turtles or Lord Dregg, but he always rescued him, and went as far as to donate his life energy to save him.Krang spends the first seven seasons in the Technodrome, either somewhere on Earth or in Dimension X, scheming to power up his battle fortress and take over the Earth.At the end of season 7, the Turtles banish the Technodrome back to Dimension X without Krang or Shredder, forcing them to work out of an old science building until they can build a new portal into Dimension X and reclaim it, which they eventually do.