[Midwesterner53]

What in thw world have they got that can tear a tank apart like that explosive did at the end of the video???

[freeandfreezing]

Most Russian tanks have weak armor over the back of the tank behind the turret. Regular anti-tank shaped charge warheads can penetrate the tank's armor there and the jet of molten metal expelled from the warhead can, and will ignite the tank's ammunition stored below that area.

When the tank's ammunition explodes the tank is destroyed in the way you can see in the video.

In this case the crew probably perished when the second drone flew under the front of the tank and exploded where they were hiding, so they missed the main explosion.

The accuracy of FPV drones makes them very dangerous to infantry, armor, and even infantry in bunkers or buildings.