AURELION SOL, Limits Broken

Flying, Hexproof, Metabolize (When I defeat a creature in battle, place a +1/+1 counter on me.)
When I transform, search your library for a card
with "Celestial" in its name, add it to your hand,
and shuffle.
You may forgo your draw each turn to search
your graveyard for a "Celestial" card and add it
to your hand.
"Celestial" cards in your hand may be cast as if
they had {0} as a mana value.