Walkthrough tips, Discussion of Campaigns [Heroes 5]

I hope I'm not mixing up the topics... I just can't figure it out myself:confused: Here, it says that the Knights can protect nearby troops with their shields (like archers). HOW do they do that? I don't understand... I know how archers use their volley fire, how the Inferno units summon gates, how griffins use their aerial strike... I know everything, I can do everything... But do the Knights have a button like the griffins and Inferno units do??? I don't remember seeing one... Or do the Knights protect on their own, and you just need to place them in front of the archers? Right?

Sincerely...