I'm thinking about taking out the High Sentinels of Arashin since they pretty much don't get played even if I draw them. I'm not sure what to put in instead so any recommendations would be appreciated.

Oppressive Rays Is a good, cheap sideboard option for aggro decks in the vein of mono-red. Erase is a fairly good sideboard card if you've got a lot of Whip or Jeskai Ascendancy decks running around where you play.

High Sentinels of Arashin seems like good card to take out since it's a bit too much mana too cast, even with Nykthos. I would suggest adding Hero of Iroas, or Eidolon of Countless Battles. Hero of Iroas makes your auras cheaper to cast and still gets heroic triggers. Eidolon of Countless Battles can get big fairly quickly since you have a lot of low mana cost creatures, can you can bestow him to get a heroic trigger on a creature, and his bestow cost can be lowered from hero of iroas. Vanguard of Brimaz is another good addition to help start making tokens, and helps pump devotion for nykthos, and can buff eidolon of countless battles too. Finally, I'd add Launch the Fleet. Nykthos, can give you plenty of mana to strive it onto everyone, giving you a bunch of heroic triggers, plus if you have eidolon of countless battles, he'll become frickin giant.

Thank you for the suggestions, I replaced the high sentinels with Hero of Iroas. The way playtesting has panned out so far I basically get 1 or 2 creatures out with a handful of instants and swing out for the win by turn 4 or 5. I haven't used nykthos for anything but its colorless mana so far, and I may never get enough devotion out to actually benefit from it. The Vanguard of Brimaz would help with devotion, but it hasn't seemed to play a part in any of the games so far and his heroic still leaves him as a 2/2. The Eidolon of Countless Battles would only really get bestowed if I had hero of iroas out to cut the mana cost, and the deck seems to work best off of 1 or 2 creatures in play so he wouldn't be as good to play as a creature. I'm kinda up in the air on Launch the Fleet the super cheap strive is amazing for heroic triggers, but I would have to take out other spells to put it in, and the other instants almost have to stay in. I may toy around with it in some play testing and see how it performs. Thanks again for the feedback.

I think the sideboard can use some tweaking. Maybe try cards like Glare of Heresy, Surge of Righteousness, Mastery of the Unseen, Hidden Dragonslayer, or Valorous Stance. I'm not a fan of Center Soul in this kind of archetype, would probably be better as one of these other suggestions. If your creatures need more protection, try Ajani's Presence instead, as at least it helps you dodge Crux of Fate. It also seems unlikely that there's a match up where you'd want to go up to 4x Spectra Wards.

Yeah, right now the sideboard is more of a maybe board. And the cards on it are a compilation of possibilities for sideboard cards. Thank you for the suggestions, I will take a look at them.

Took out Phalanx Leader for Lagonna-Band Trailblazer. The leaders are great, but I seldom get more than 2 creatures out and he's vulnerable to turn 2 burn spells where the trailblazer is not. I'm thinking of taking out ajani for Ajani's Presence for extra protection. If I do that I may drop to 18 land for a play set of it.

Hey man, nice deck. I would consider dropping a couple of the buffs for some Seeker of the Way. He gets buffed when you buff other guys and can net you some life. With my Mono White Devotion I feel like I often would rather have an extra creature of the extra buff spells. Opponents have lots of ways to kill guys even with protection and topdecking a Gods Willing after a board wipe is seriously lame. Other than that, +1 from me.

Hmm, also, I think Spectra Ward is way too expensive. I would suggest some extra removal, like Banishing Light. It has the extra benefit of being able to hit planes walkers, enchantments, and anything indestructible or otherwise troublesome.

I like the seeker suggestion, do you think I could swap in 2 copies of him for 1 copy of 2 other creatures and keep the instants? I'm trying to keep the protection spells in for the pierce otherwise I can just get chump blocked all game. And thanks for the +1.

Honestly, I do think it would work better with a few less spells but if I were going to cut creatures I think it would be Hero of Iroas.

The only two Auras aren't really worth shaving only 1 off of. Ordeal of Heliod is already cheap and unless you have 3 hero's out Spectra Ward is always gonna be too expensive with only 20 lands. I would suggest taking two Hero's and both Spectra wards out for 4 Seekers. Seeker is just so useful in a deck like this.

I'm torn about the spectra wards. On the one hand I don't know how likely I'll be to pull 5 out of 20 lands to play it. On the other hand, if I do get the lands it gives me a finisher. I think I'll play test taking out the spectra wards, 1 Hero of Iroas and 1 Fabled Hero for 4 seekers. Banishing Light is going into the sideboard for situational removal. All of the games I've played so far have been really aggressive and lasted 4 or 5 turns so removal seems like it would be very situational. Thank you for the suggestions.

The seekers don't seem to be doing as much work as I'd like if I'm gonna have 4 of them. So I dropped 2 of them, dropped Fabled Hero to 2 cuz he's more vulnerable on his first turn out than the others, upped Hero of Iroas back to 4, and added 2 Battle Mastery to keep my double strike numbers the same.

It seems good but without the blue or bant your gonna get roadblocked alot I'd recommend bant because of DDromoka's Command is so great with this deck removal and two heroic triggers

It would also double the cost of the deck and force me to use more lands just to be able to reliably hit the colors.

Mortal Obstinacy is the most boss way to deal with enchantments in a heroic deck. I'd run 1-2 of them before running the first Erase. Glare of Heresy is another good SB card that takes care of Elspeth, Sun's Champion, Siege Rhino, Chained to the Rocks, and other not-fun white cards. Mortal's Ardor is another good card to bring in against red decks. I'd also recommend adding 2 more Fabled Heros to your SB to bring in additional threats against control decks. I'd remove the Erases, some BLs, and a number of Center Souls and Oppressive Rays to make space for the cards I mentioned in your SB. Hope some of that helps!

Killer suggestions GeminiSpartanX thank you, I've been kinda stuck on the sideboard and this helps a lot.

After some play testing I've determined that I hit 5 lands, or 4 and a Hero of Iroas enough to put Spectra Ward back in. It should give me the pierce I need against multiple mono colored creatures.

I like Spectra Ward a lot in heroic, but only as a 1-of. You could replace one of them with a Heliod's Pilgrim to avoid drawing into 2 but still having the option of grabbing one with the pilgrim if needed. That way if you draw into your Ward you can search for and equip the ordeal or the double strike depending on what you need.

Dude, I can't even express how incredibly helpful you've been.

No problem. Let me know how you do at your next FNM!

Will do, just moved to a new city and haven't looked for a shop yet. Plus I gotta order the cards so it'll be a few weeks, but I've got a good feeling about this deck.

Tweaked a tiny bit more taking out Seeker of the Way completely. Replaced him with a 3rd Valorous Stance and second Heliod's Pilgrim for the aura search.

Have you tryed Ajani Steadfast ? Seems like it would be good in here

I have, I liked him and may put him back in. My only concern is that if I put him out on turn 4 I have no mana open to protect my guy.