Bladecoil Serpent (229s) [The Brothers' War Promos]

When this creature enters, for each {U}{U} spent to cast it, draw a card. When this creature enters, for each {B}{B} spent to cast it, each opponent discards a card. When this creature enters, for each {R}{R} spent to cast it, it gets +1/+0 and gains trample and haste until end of turn.