First days of the German operation "Blau" in the summer of 1942 in the Oskol river area. The Wehrmacht 6 Army dealt a crushing blow at the boundary of the 28 and 21 RKKA Armies, resulting in loss of control of 28 A units. Soviet rifle divisions are retreating to the Oskol river crossing in Staro-Ivanovka area. In order to allow the Soviet forces to break away from the enemy, the 28 A command assigned the composite detachment of 13 TC a mission to hit the advancing enemy forces from the flank. • Two operations of 6 turns for each of the parties. • 369 Croatian reinforced infantry regiment within 100 LID. • Precisely recreated area of over 40 sq. km: hilly plains with harsh terrain and extensive gullies. • Historical organizational structure of units at the time of the offensive.