Advice needed: Daemons versus Imperial Knights
As midnight said, lash of submission princes (preferably with iron arm) will make short work of it. Plaguebearers would too, however unless he's barreling it into your lines it'll be hard to get them in close combat. With princes having a very high initiative, you have good odds of smashing it down once weakened. Also remember it'll be retaliating with 3 attacks hittin on 5+, so it could whiff completely.
Alternatively; ignore it. It's shooting is meaningless to you for the most part. Throw a large unit at it to buy a turn or two.
Last edited by Ravner298; 04-11-14 at 06:44 PM.