Kazei participated in many important operations, sabotage. For example, in 1943, the boy brought reinforcements to his encircled detachment in time, thereby he managed to save the lives of his combat comrades-in-arms. But the last fighting day for the young warrior was May 11, 1944. Then Marat and the commander of the reconnaissance company came to the village of Khoromitsky to meet with a messenger. But the house where the partisans stopped was surrounded by the Germans. Larin, who was trying to get out the window, was struck by a line from a machine gun. The boy hid behind a tree and fired back to the last, until the cartridges ran out. He let the Germans get closer to him in order to pretend that he was surrendering. But then Marat quickly grabs a grenade, pulls out the chick and blows himself up along with the Germans. For numerous feats, for torment, the young Belarusian warrior was awarded the title of Hero of the Soviet Union.