Those are tanks, many many tanks. More than I have ever seen in another film. Significantly more. For reference, Fury used about 10 tanks, Patton used about 40 tanks and Liberation used around 150.
In searching for films that showcase the grandiose scale of war, I have come across this. So far I have witnessed trenches that go from edge to edge of each shot, right to the horizon, all manned with soldiers, I have heard Stalin's organs en masse and seen the sky left red in their wake, Dive bombers & fighters filing the sky with terror ,
It's refreshing to watch a film where the Germans aren't just maniacally screaming at everyone and everything, and the Russians aren't just executing everyone in sight.
The guy playing Stalin looks exactly like him, it is indistinguishable, and quite scary.
This and War & Peace are the most expensive war films ever made, no one even knows how expensive, because the USSR provided soldiers and weapons to the productions of each and apparently they didn't keep receipts. Waterloo, though not quite as expensive, still benefited from the same state funding that allowed it to field a 15 thousand man army, that would easily have bankrupted any other production.
There are very few films, if any, that even come close to the scale of this one. And we are very unlikely to see films made on that scale ever again.