Alistair ducks the snowball. It would have missed if he hadn't ducked, too, but don't tell him that; he gets that one brief moment of satisfaction, ha, before he straightens up to find the source, possibly planning to say that ha out loud, and discovers that said source is heading toward him at full speed.

He has time to lift his padded shield and say, "Can't we--" before impact. The last word would have been negotiate.