Yup, it's a typical (albeit frustrating) phase. I have had biters, and my typical response is that the child is removed from the situation (which teaches that biting=no more playing for a period of time) and I get down to their level and FIRMLY say "We don't bite. Biting HURTS." Then the child will sit away from their buddies for a minute or so. (Go ahead and call it a time out, I do!) I remind them one more time, (slightly "nicer" voice this time) "No more biting our friends, its OWIES!" or some such thing, and bring them back to the group.
If it's becoming a habit, then unfortunately the shadow thing is necessary, for the other kids' sake. Make sure too, that it's not happening due to other children getting right up into his face. I had a little guy that was like that. His "bubble" of personal space was really important, and he didn't hesitate to let others know!