Caliber.50 Mega Drive

You play as Captain Addis, a former officer in the US army during the Vietnam war. Now, twenty years after the war, you are sent on a mission to follow the Ho Chi Minh trail and to rescue American airmen that were left behind. In this action game, you navigate your character in top-down view and continuously fire at enemies, turning him in different directions, since he doesn't always face the direction he is moving in. You can for example walk backwards, firing at the enemies who pursue you. Enemies include not only various types of gunmen, armed with rifles, flamethrowers, or grenade launchers, but also tanks and helicopters. You can blast open crates to find ammo and supplies. Defeated enemies also leave you items.