A main battle tank (MBT), also known as a battle tank or universal tank, is a tank that fills the heavy direct fire role of many modern armies. They were originally .br A main battle tank (MBT), also known as a battle tank or universal tank, is a tank that fills the heavy direct fire role of many modern armies. They were originally .br Ukraine military unveils new Tank to scare Putin A main battle tank (MBT), also known as a battle tank or universal tank, is a tank that fills the heavy direct fire .