Celestus Sanctifier

If it's neither day nor night, it becomes day as Celestus Sanctifier enters.
Whenever day becomes night or night becomes day, look at the top two cards of your library. Put one of them into your graveyard.

Gavony Dawnguard

Ward {1}
If it's neither day nor night, it becomes day as Gavony Dawnguard enters.
Whenever day becomes night or night becomes day, look at the top four cards of your library. You may reveal a creature card with mana value 3 or less from among them and put it into your hand. Put the rest on the bottom of your library in any order.