Ascension

All cards in your deck must have {p/b},{p/c},{p/g},{p/r},{p/u}, or {p/w} in their mana cost.
Whenever you cast a card with {p/b},{p/c},{p/g},{p/r},{p/u}, or {p/w}, gain 2 life.
What's a little life force in the grand scheme of things?