Voted for Divine Stallion and Invigoration for more ways to stall. The up side is that you stall really well, the downside is if you have a pure stall deck, battles can range over an hour on a bad pairing in PvP. So, I definitely see that I can use them in game.
The other two I voted for were Morning Sun and Transcendence, both having ways buff up your creatures even more conveniently, with the second one having much more potential.