18 As the enemy came down toward him, Elisha prayed to the LORD, “Strike this army with blindness.” So he struck them with blindness, as Elisha had asked.

Read 2 Kings 6:18 Using Other Translations

And when they came down to him, Elisha prayed unto the LORD, and said, Smite this people, I pray thee, with blindness. And he smote them with blindness according to the word of Elisha.
And when the Syrians came down against him, Elisha prayed to the LORD and said, "Please strike this people with blindness."So he struck them with blindness in accordance with the prayer of Elisha.
As the Aramean army advanced toward him, Elisha prayed, “O LORD, please make them blind.” So the LORD struck them with blindness as Elisha had asked.