Archaios, The Progenitor

When Archaios, The Progenitor enters the battlefield, for each {u}{u} spent to cast it, draw a
card.
Similarly:
For each {b}{b} spent to cast it, target player mills
5 cards.
For each {r}{r} spent to cast it, Archaios, The Progenitor deals 2 damage to target creature.
For each {g}{g} spent to cast it, put two +1/+1
counters on target creature you control.