This is the 434th most frequent Ukrainian word.
контрнаступу
"Counteroffensive" – a military action in response to an enemy attack.
In this sentence, 'контрнаступу' is again in the genitive case, showing possession belonging to 'стратегія', referring to the strategy regarding the counteroffensive.
Сьогодні була оприлюднена стратегія контрнаступу.
Today, the strategy of the counteroffensive was published.
Here, 'контрнаступу' is in the genitive case, denoting the object related to 'деталі', which are relating to the counteroffensive.
Деталі контрнаступу залишаються секретом.
The details of the counteroffensive remain a secret.
Here, 'контрнаступу' is used in the genitive case to indicate possession or readiness related to the counteroffensive operation.