Mega Man, the Blue Bomber

When Mega Man, the Blue Bomber enters the
battlefield, you may exile target artifact you
control. Put a number of +1/+1 counters on
Mega Man, the Blue Bomber equal to the
converted mana cost of the exiled card.
{u}: Mega Man gets -1/+1 until end of turn
{r}: Mega Man gets +1/-1 until end of turn.