Sunbond is going to be way too difficult to get working because the only life-gain card you have is Gift of Orzhova . You should either commit with more life-gain tricks or switch it out for something else.
Anyways, I playtested this against my Standard Modern Jund: Welcome back DRS! deck, which has strong removal, and I went 4-1 against it. It seemed like you needed more protection since I was able to remove everything before it got out of hand, and Gods Willing was almost always my target for Thoughtseize . The one game you won was one where you got 3 Gods Willing and a Gift of Orzhova and were thus able to thwart my removal and bypass my creatures, and as I recall it was a Hero of Iroas that wasn't any bigger than 6/6. Since you're already maxed out on Gods Willing , you may want to add a couple copies of Brave the Elements or perhaps Boon of Erebos if you'd rather have a Heroic trigger and a way to survive Supreme Verdict .
Also, Sunbond was a completely dead card in the matchup. It always sat in your hand, got Scryed to the bottom, or was an overcosted Heroic trigger that did nothing. So that would probably be the first place I would recommend to cut to make room for more protection. Without Sunbond , you may want to switch out Ordeal of Heliod with Ordeal of Erebos since forcing your opponent to discard will be much more relevant in most matchups than life gain. In fact, in one of the games, you got over 30 life before I stabilized and it still didn't matter in the end since my board state was too dominant to come back from even if you had 100 life. Silent Sentinel was also never a factor in any of the games, as if it ever got to a point where you had 7 lands, the game was already over.
Finally, I would keep an eye on Odunos River Trawler . It was definitely a horrible matchup for that card since my deck has Deathrite Shaman and Scavenging Ooze to keep him from doing anything, but even then it seemed rare that its effect would be relevant even if the graveyard hate wasn't there. I would be tempted to fill that slot with Fiendslayer Paladin for a 3-drop with Lifelink and its own built-in protection from most of the format's good removal.
Otherwise, I enjoyed playing your deck, and the core seems really solid. Good luck! +1
I really like the way this deck looks, using the playtest button I got the feeling that it's a really fun one to play. I didn't experience any situations where a creature got to 9/9 or higher by turn 4 though...
Here are some of my thoughts on the deck:
If you don't care about the extort ability on Blind Obedience , then you could also consider Imposing Sovereign for your sideboard instead. It wouldn't benefit Ethereal Armor , but it would benefit Eidolon of Countless Battles . Personally I'd rather benefit the Eidolon over the Armor, since it can keep existing even after the attached creature dies. Sovereign does have burn vulnerability too I suppose, but on the other hand it can be used as a blocker in an emergency (or a platform for your auras if you find yourself without other creatures to do so).
On another note, you're running a lot of spells to target your own creatures. With that in mind I think you should look into running Fabled Hero , it's a good way to get more value out of powering up your own creatures (especially with bestow).
On the topic of Sunbond , if you're willing to shell out the cash for it, or can trade for it, Archangel of Thune should not be overlooked. I know Hero of Iroas won't make her easier to cast, but she's just sooooo much better. Also, with cards you've already got going, I'd just swap one Sunbond out for a Gift of Orzhova from your sideboard, it'll give you a little bit more evasion.
I also see you're considering Silent Sentinel , the main question is do you want the games to go that far? The costing of most of your cards says you might not be interested in letting games reach the point where 7 cost cards are played, but if you do, it certainly wouldn't be out of place with how many enchantments you have.
Finally, while playtesting I frequently enough found that I didn't have enough black mana. The best way I can figure to remedy that is to swap out some of your Plains for some copies of Godless Shrine (or if you don't want to spend the money I suppose you could go with Orzhov Guildgate , though I wouldn't).
All in all, this deck feels great and I think there's a lot you can do with it. I hope my input is of use to you.
Really appreciating these comments! What creature would I replace for Fabled Hero or Imposing Sovereign ? Definitely gonna keep Silent Sentinel out of the deck completely. Archangel of Thune is insanely good, but not $40 a pop good. I'd run Godless Shrine , but I'm trying to keep this as Theros/BNG as possible so I don't have to change much when RtR and M14 roll out. I've found that the Sunbond is actually extremely effective with the Fiendslayer Paladin now in and all the other lifegain cards.
I still haven't been able to test this deck against other decks because I'm still missing about 10 cards, but they'll be coming in sometime in the week and I'll have a much better idea on how this deck holds up. I've been playing without the Hero of Iroas and the Eidolon of Countless Battles which are the backbone of the deck and it's still fared quite well against my friend's FnM decks.
I've also found that Vanguard of Brimaz (mainly the vigilance effect) is really good. The heroic also makes the tokens which pumps of Eidolon of Countless Battles . Maybe that instead of Odunos River Trawler or Spiteful Returned ? Or perhaps a couple Heliod, God of the Sun ?
If Spirit of the Labyrinth isn't especially important to the deck, you might explore using those slots for Fabled Hero . As for Imposing Sovereign , I was suggesting that you put it in your sideboard where you currently have Blind Obedience .
I have something similar and bestow in the tits,.+1 Roar of the King is mine.
Nykthos, Shrine to Nyx ? It mana filters and ramps y'know.
Have you thought about putting 2 Xathrid Necromancer s in here? It looks like it would be really good in this deck
There really isn't enough life link in the deck to warrant Sunbond . I am building this deck but I am main boarding 4 Fiendslayer Paladin s and i will probably move it more around life link and sunbond which are super good
Maybe put it two more Soldier of the Pantheon main board. It's the only 1 drop creature here and 2/1 is great for the mana especially with pro multicolor
Have you thought about Obzedat, Ghost Council or Blood Baron of Vizkopa for sideboard? I've been playing with them in my side and found them EXTREMELY helpful with Sunbond . The massive amount of life sway they provide doesnt hurt either.
I'm trying to steer clear of the RtR block as much as possible so I don't lose a bunch of cards when it rolls out. That and Blood Baron of Vizkopa wouldn't be able to be enchanted by anything.
Also one other thing to consider is Orzhov Charm . Normally it is not as good as the other charms but in this kind of deck it can shine. I have found in games because of my lifegain it is decent removal. The first ability allows me to save a creature/restack enchants. I have even used the last ability to return a Hopeful Eidolon when I was in a pinch.
If you want you can check out the deck like this I have been working on Orzhov's Voltron.