Updated 12/29/16

Commander
Selvala, Explorer Returned

Creatures - 18

Lifegain
Essence Warden
Soul Warden
Soul's Attendant
Herald of the Pantheon
Rhox Faithmender
Student of Ojutai

Card Draw/Advantage
Argothian Enchantress
Femeref Enchantress
Mesa Enchantress
Verduran Enchantress
Eidolon of Blossoms
Karametra, God of Harvests
Soul of the Harvest

Pillow Fort
Silent Arbiter

Other
Children of Korlis
Recruiter of the Guard
Rune-Tail, Kitsune Ascendant
Felidar Sovereign

Enchantment - 22

Lifegain
Authority of the Consuls
Lifegift
Leyline of Vitality
Angelic Chorus
Boon Reflection
Righteous Cause

Card Draw/Advantage
Exploration
Sterling Grove
Sylvan Library
Enchantress's Presence
Angelic Accord
Into the Wilds
Sigil of the Empty Throne

Pillow Fort
Righteous Aura
Dueling Grounds
Ghostly Prison
Sphere of Safety

Other
Mana Bloom
Rest in Peace
Celestial Convergence
Test of Endurance

Instant and Sorcery - 10

Lifegain
Beacon of Immortality

Removal
Path to Exile
Swords to Plowshares
Day of Judgment
Fate Forgotten
Wrath of God
Return to Dust
Fumigate

Other
Intervention Pact
Enlightened Tutor
Gaea's Blessing

Artifacts - 11

Lifegain
Ivory Tower
Angel's Feather
Tablet of the Guilds
Wurm's Tooth
Aetherflux Reservior
Alhammarret's Archive

Other
Elixir of Immortality
Expedition Map
Bow of Nylea
Crystal Chimes
Venser's Journal

Land - 38

Pillowfort
Mystic Maze
Kor Haven
Maze of Ith
Thespian's Stage

Multicolor
Blossoming Sands
Brushland
Canopy Vista
Command Tower
Graypelt Refuge
Krosan Verge
Selesnya Sanctuary
Sungrass Prairie
Sunpetal Grove
Temple Garden
Temple of Plenty
Windspept Heath
Wooded Bastion
Yavimaya Hollow

Other
Arcane Lighthouse
Glacial Chasm
Kabira Crossroads
Mistveil Plains
New Benalia
Reliquary Tower
Sapseep Forest
Wirewood Lodge

Basic
4 Forest
8 Plains

The core strategy is simple: Lifegain. Card draw. Test of Endurance or Felidar Sovereign.

I've gone for a pillowfort-style defense, adding a suite of mazes and combat damage prevention to combat commander damage kills. This had proven to be the major weakness of the deck in the past. Erebos and other "players can't gain life" effects are also a concern, and I've added some spot Enchantment exile to combat these cards since all but one are Enchantments.

What else should I think about? What other threats should I plan for?

Thanks!

I didn't notice any graveyard hate in there. Rest in Peace is on-theme, and you could (and probably should) run some tutors for your wincon, like Idyllic Tutor or Enlightened Tutor, which could also find RiP if needed.

There's some other "Players can't gain life" effects out there, but Erebos is the only one I usually see (and he's not usually there to block lifegain - that's just a nice perk), so you probably don't need to worry about that.

If Sorin Markov / Magister Sphinx see a lot of play in your area, you might give some thought to effects that give you shroud/hexproof personally.

RiP is a good choice, thanks! I'll think about what to replace.

Tutors are something I might add, but they're all on the expensive side, except Worldly. I generally try to stay away from $10+ cards unless they're critical to the deck. If I find my answers aren't turning up reliably I might add them.

A quick search of "can't gain life" cards (which I han't really bothered to do before) indicates that all but two are Enchantments and therefore vulnerable to the same cards I included for Erebos. One of the others, Skullcrack, is just a one turn effect. Stigma Lasher could potentially ruin my day, but it's just a 2/2 for 2 without evasion or haste, so I feel have enough answers to that already.

Wait.... *checks SCG*.... when the hell did Idyllic Tutor become a $15 card?

It spiked pretty hard in preparation for Journey Into Nyx, apparently, to around $20. It hasn't gone down too much since, probably due to a number of factors: decent EDH sales, not a popular card when released, in a small set which wasn't wildly popular overall (save a few cards, obviously), and all the dorks who bought into it before JIN are looking to get most of their money back. There's some viability in Modern for it in the Restore Balance deck, but the Restore Balance deck isn't Tier 1 so this is unlikely to contribute much to the cost.

Yeah. It was already $10 when I got back in around Dragon's maze, IIRC. Ah, to have my old collection back... I guess the random binder my parents found with 4 ABUR duals is as much as I could hope for.

I like where you are going with this deck. Get that Serra Avatar a place. There is nothing more satisfying then dropping a 100/100 creature on the board and watch people flinch

Celestial Mantle is a must for any white life gain deck.

You are running a ton of enchantment cards I would drop Command Sphere for Crystal Chimes.

Silent Sentinel is also a decent option since Sun Titan can be pricy.

I have gotten good use out of Ordeal of Heliod. It combos crazy with Silent Sentinel or Sun Titan and gets you a ton of life and some +1/+1 counters as well.

I know this last one is pricy but trust me if you can find a Archangel of Thune for a decent price you will wreck things. I have one in my Oloro deck and it always pays out.

I think Sigil of the Empty Throne would work well for your deck.

You definitely don't have enough artifacts for Golem's Heart so unless your opponents are playing heavy artifact decks that one might be worth cutting. Same with Leonin Elder.

Another option for graveyard hate is Ground Seal. It doesn't stop everything but it's nice that it can always just draw you a card.

Selesnya Cluestone is at a kind of awkward mana cost since it costs the same as your commander. It can cycle but that costs 6 mana so its pretty slow. You might want to replace it with a 2 mana rock like Selesnya Signet or Talisman of Unity.
Another option is to use a ramping enchantment such as Mana Bloom which also works nicely with your enchantresses. You can cast it for 1 to draw and it goes back to your hand the next turn.

I like Sigil and Mana Bloom, those are great suggestions. Definitely going in. There are 14 Artifacts right now including the lands, but I see your point about the Heart and Elder, particularly in light of the fact I probably wouldn't be at too much of a disadvantage by ditching the rocks altogether. Then the Artifact Lands could go - they really just enabled the Heart and Elder. I think when I need graveyard hate, RiP is a better choice than Ground Seal.

Crystal Chimes is another that definitely needs a home; it's particularly nasty to drop after a Fracturing Gust. There are indeed a bunch of Lifegain cards that are attack triggers. I'm trying to steer clear simply because I don't really want to be attacking with this deck. I'm looking to play very defensively since the deck relys on alternate wincons. Noble Purpose is getting cut for the same reason. Not to say that opportunity strikes are out of the question, but not unless my defense is buttoned up tight.

-Commander's Sphere
-Selesnya Signet
-Leonin Elder
-Golem's Heart
-Noble Purpose
-3 Artifact Lands
+3 Basic lands
+Rest in Peace
+Sigil of the Empty Throne
+Crystal Chimes
+Mana Bloom
+Ghostly Prison

Actually I think Sphere of Safety should be in instead of Ghostly prison. The extra cost is more than justified in this deck I think. Plus I already own it.

What would people think of replacing Orim's Prayer and Noble Cause with more pillowfort-y cards like Deuling Grounds and Spiritual Asylum? I'd like to keep Righteous Cause - to benefit from the misery of others, of course.

I'd go with Privileged Position over Spiritual Asylum.

From a straight power level, I'd agree. It's a better card with a wider net, hexproof instead of shroud, and just 1 CMC more. I still prefer Asylum because of the political aspect - it says right on the card I don't plan on attacking and that should mean my opponent's threatmeters go up far less than they would if I dropped Privileged Position. And, y'know, it costs a twenty-fifth as much in real money.

Okay, so one more round of changes then it should be able to sit for a bit:

-Orim's Prayer
-Noble Purpose
-Noble Stand
-Ghostly Prison
+Dueling Grounds
+Spiritual Asylum
+Sigil of the Empty Throne
+Sphere of Safety

I'll be taking this to Commander night tonight, so we'll see how it goes. A few things are still in the mail, so I'm missing Sigil, Dueling Grounds, Spiritual Asylum, RiP, and the Chimes, but what I have is just fine. I did toss a Tormod's Crypt in for the RiP.

It might even need toning back or some extra hugs to be properly political. A few days ago I ended a playtest after eleven turns with 138 life and a Test of endurance in play. Final turn was a Fracturing Gust for 16 life and 8 cards from Femeref Enchantress, a Day of Judgement with Twilight Shepherd in play, two Soul Sisters, and Test. Exploration is fun. (Insert disclaimer about reading into too much from solo playtests here.)

This deck is gross. Selvala's ability gets ridiculous at 4 player. And the lifegain has to be seen to be believed.

Game 1: Vs. Brimaz, Daxos, and Vorel

This game was very short - maybe 30min. After taking two swings for all from Brimaz and an attack from Vorel, Brimaz saved me the trouble of casting my Wrath because she was getting tired of having me gain 4 per creature from my Soul Sisters. I cast Felidar Sovereign at 74 life. No one had answers before my turn.

Game 2: vs the same Brimaz, Tsaigur, andKarador.

This was a much longer game. Brimaz almost had us all - Brimaz with Sunbond and 80+ counters due to True Conviction knocked out Karador after she decided not to go for the kill on me due to feeling like she was ganging up too hard. Got me down to 27 at one point. Then an overloaded Cyclonic Rift happened.

Tsaigur and I then made an informal alliance where I was getting him the cards he wanted from his GY in exchange for help with the kitties. He ended up killing Brimaz with commander damage. This was lucky for me since Brimaz had dealt 18 commander to me by then. Then I drew Test of Endurance. Got Cyclonic Rifted. Cast again. He swung for everything, dealing 57 damage to me (largely with Consuming Abberation) and leaving me with a paltry 117 during my upkeep.

It's been a bit. This deck continues to impress, except in one area. It's incredibly vulnerable to commander damage. So I've decided to add a few answers in that regard. I'm also considering removing the Visions bouncelands because they lack the utility of the Ravnica bounces (i.e. they can't bounce tapped lands, and they can't bounce refuges).

+Maze of Ith
+Kor Haven
+Ice Flow
+Safeguard
+Plains

-Jungle Basin
-Karoo
-Suture Priest (I like her, she's useful, but she's the only source of damage in the deck, and that's always bothered me flavorwise)
-Rites of Flourishing
-Celestial Force

Any further suggestions?