Around that time, Zhuge Ke, a general from Wei's rival state Wu, was stationed at a military garrison at Wan (皖; around Qianshan County, Anhui) and posed a threat to the Wei forces in the region. When Sima Yi wanted to lead troops to attack Zhuge Ke, many officials advised him against it. They said that Wan was heavily fortified and abundant in supplies and that Wu reinforcements would come to Zhuge Ke's aid if he came under attack, thus putting the invaders in a perilous position. Sima Yi disagreed and said: "The enemy is adept at naval warfare. Why don't we try attacking their land garrison and see what happens. If they know their strengths, they will abandon the garrison and retreat; this is our objective. If they hold up inside the garrison and defend their position, their reinforcements will have to reach them via land because the waters are too shallow in winter for boats to sail through. In doing so, they will be putting themselves at a disadvantage because they aren't as good in land-based warfare as us."