High Quality Content by WIKIPEDIA articles! The Landkreuzer P. 1000 Ratte (lit.: Land Cruiser P. 1000 "Rat") was a design for a huge tank for use by Nazi Germany during World War II. It was designed in 1942 by Krupp with the approval of Adolf Hitler, but the project was canceled by Albert Speer in early 1943 and no tank was ever completed. At 1,000 metric tons, the P-1000 would have been over five times as heavy as the Panzer VIII Maus, the largest tank ever built.