After the unsuccessful diversionary attacks Operation Dawn V and Dawn VI in southern Iraq, Iran opened a front at the lakes of the Hawizeh Marshes. 250,000 Iranian troops swept through the Iraqi desert and were met by a mechanized force that slaughtered them. Iran needed air-support but lacked spare parts for its American-made planes. This became a serious problem for Iran and led to heavy casualties.
Iran enjoyed a zealous force of Pasdaran and Basij, but could not replace their deaths, forcing them to rely on artillery, air-support, and tanks.
On February 14, 1984, Iran fought through Iraqi defenses to the oil-rich Majnoon Island. Iran now was ready to launch the final attack of the Battle of the Marshes. A loss would allow Iraq to regain all territory lost in the battle. Operation Kheibar was Iran's first strategic offensive. The IRIAF could only provide an inadequate 100 combat sorties per day on average. The Iraqi Air Force had their hands full on the southern front. Because of Iran's lack of aircraft, they used helicopters to support their troops. Eventually the Iranians swept across the marshes and forced the Iraqis out of the Majnoon islands - a major disaster for Iraq.
In the end Iran suffered 20,000 casualties in the battle of the Marshes and only inflicted 10,000 casualties on Iraq. But for Iraq even 9,000 was an unacceptable number. After the battle, Iran tried unsuccessfully to take the Baghdad-Basra highway with Operation Badr. At the end of the War, Iraq expelled the Iranians from Majnoon island by using professional combined-arms tactics coupled with chemical weapon attacks