Released back in late 2011, World of Tanks 0.7.0 only had three tech trees, different physics and spotting mechanics, there was no arty cap, no stun, and more. Those who were not around to play it back then and those who would like to travel back in time can play it until April 3 as World of Tanks Classic.
https://www.notebookcheck.net/April-Fools-Day-2019-World-of-Tanks-0-7-0-goes-live-once-again.415345.0.html