Saruman's Vanguard

When Saruman's Vanguard enters the battlefield,
create a 2/2 black Uruk-hai creature token with
first strike.
Whenever an Uruk-hai enters the battlefield
under your control, you may sacrifice it. If you
do, you draw X cards and lose X life, where X is
the sacrificed creature's power.
"Meat's back on our menu, boys!"