Hell's Gate

From the introduction -
"This is a simulation game of the battle of the Korsun pocket in Ukraine in January and February 1944. Two players or teams direct the actions of the German and Soviet forces as they seek to capture or regain territory and to inflict losses on the opposing forces while minimising their own losses."

The Russians try to create a pocket, and then destroy the German forces, while the Germans sek to free their trapped comrades. Simple, but subtle mechanisms, reflect trade offs between all out attacks and greater losses, and the mobility of armoured units.