The Hundred Days Offensive Jul–Nov 1918 was the costliest
The Ludendorff offensive other wise known as the spring offensive was a German offensive on the Western Front intended to win the war before the American troops that had begun arriving in France could fully deploy.
I'm unsure of how far they advanced
Kaiserschlacht was the last German offensive and was a series of German attacks along the Western Front.
The nuclear arms race was an arms race competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War.
Vietnam War also called Second War of Indochina, was a war fought between 1955 and 1975 to prevent the reunification of Vietnam under a socialist or communist government. In this war the Republic of Vietnam (South Vietnam) participated, which was against the communists, with the support of the United States and other allied nations of the United States against the local guerrillas of the National Front for the Liberation of Vietnam ( Viet Cong) and the Army of the Democratic Republic of Vietnam (North Vietnam), backed by China and the Soviet Union.
The battles that took place during the conflict occupied the entire territory of Vietnam, the main characteristic of these battles is that they occurred in an area of dense forests, full of natural elements and animals that made the operation of the army of the USA difficult. We could say that this factor greatly favored the army of North Vietnam, since they knew the battlefield perfectly.
If I remember right, it is "The Camp David Accords"
