Elefant

The SdKfz 184 Panzerjäger (Tank destroyer) Elefant, originally named Ferdinand, is a German tank destroyer used widely in the Eastern Front. The tank destroyer is famous for its nearly impenetrable armour and firepower. It has the largest kill per loss ratio (10:1) of all German tank destroyers during the war, making it one of the most effective ground vehicles in World war II.

Call of Duty: United Offensive
The Elefant appears in Call of Duty: United Offensive in the campaign mission 'Trench' where the player must use explosives to blow up three of them. The Elefant also appears in limited numbers in multiplayer. he Elefant is the German's counter to the SU-152. It has incredible health, being able to resist many tank shots before being destroyed. Its cannon can take out a T34 or Panzer in one shot. However, it's very slow, it's cannon is horribly inaccurate past short range and the cannon can't be moved independently of the treads. Even though it has incredible health, don't try to take on every enemy tank at once. You'll get seriously injured, if not killed.