The Panzer VIII Maus is the largest tank ever built by the Germans in World War II. There were designs for larger tanks, but only the Maus ever made it to production, although only 2 were produced. It is unclear if the Maus ever saw combat action as there are mixed reports.
The Maus will now see action in Supreme Commander: World War II. Take a look at the images of the size of the beastly Maus.