Volstadt, Angel's Bane

Favored Enemy —Angel (This creature gets +2+2 if it blocks or becomes blocked by an angel creature.)
Tap three other untapped knights you control: Target creature becomes an angel in addition to its other types.
Whenever Volstadt kills an angel, put three +1+1 counters on him, then create X 1/1 white and black knight creature tokens where X is the number of +1+1 counters on him.