1) Tutelage. Defining a whole archetype is VERY powerful.
2) Oath of Nissa. Green Ponder? Yes, please.
3) Fevered Visions. Strong anti-control tool; unfortunately not well-placed currently.
4) Tezzeret's Touch. Not quite Ensoul Artifact, but getting the artifact back upon removal is pretty great as well.
5) Angelic Destiny. Recurrable threats are amazing; this definitely fits the description.
Honorable Mentions: Always Watching, Evoleap, Call the Bloodline.
Also there are some enchantments I want to like,but they are just too slow (Hidden Stockpile, Ulvenwald Mysteries).
This guy nailed it. I might consider putting Fevered Visions lower because you don't want to play it against all those agro decks that can play out their hand quickly and then you just keep fueling them. Plus, it is typically used as support for Tutelage. Actually, maybe I'll take it out all together for Valor in Radkos as that is another that decks are built around and can end the game quickly and out of nowhere.