At the end of the war there was only one prototype built and two more in production, IIRC. The Maus was indeed the biggest German tank of WW 2, which has been built, at least only 1. It never saw a combat. Although having a weight of 150 ts!!! this tank was relative fast with 27 kmh. With his big guns and armour such a vehicle would be used at best in attacking heavily fortified areas. But also in defense such a vehicle would be an impossible task for even three Sherman or T 34 platoons. Nevertheless the resources in developing and producing such a monster would have been better used in smaller vehicles like Panther 2. About German humor: It is not very common, but we do have a sense for humor, not so black like the British, but we have. The first name of the Maus should be Mammut but this was changed very quickly into Maus.
Adler