Maus

Fig 1

Fig 1 shows the front of the German Maus, a tank that never actually saw combat.  Only 2 were ever built.  The main gun is the massive 128mm anti-tank gun, and instead of the normal co-axial machinegun, it has a 75mm anti-tank gun.  This tank was HUGE.  Nothing would have been able to stop this in a face to face fight.

Fig 2 shows the intricate suspension that was needed to support this behemoth.  The Germans has a similar tank called the E-100 that was basically designed to use the same chassis, but with a different turret.  No E-100s were ever actually built.

Fig 2