Mastery of the Unseen would be nuts with Altar of the Brood.

At first glance and playthrough I like it. Very nice synergy - I have played Constellation before it became popular, but I used a lesser known card Skybind to repeatedly trigger Siege Rhino and Gray Merchant of Asphodel. BUT i like the Altar of the Brood style, and I feel if altar of brood gets destroyed you can still beat them down because you have a decent amount of versatile threats.

3 things I noticed real quick though:

I wouldnt use Drown in Sorrow sideboard. your maindecking Doomwake Giant you will wreck Aggro already. save that slot for a weaker matchup.

and i would run at least 2 Elspeth, Sun's Champion

I would get rid of Suspension Field and run Hero's Downfall and Thoughtseize mainboard, and you can add Duress to sideboard against Control.

Also Whip of Erebos would probably be a good addition

Ihazadeck

Mastery of the Unseen seems good specially when I flip pyxis, it will trigger its ability (I guess). However, I have more pyxis to exile my cards in my library to mill myself late game.

SpikedEggnog

I followed some of your suggestions and I felt even better running this deck. More suggestions will be great because I want to use this deck in money matches (and this deck becomes a rogue deck haha lol)

Ok I saw that it's looking better and more versatile.

Im still thinking you need to try and squeeze some copies of Hero's Downfall in there or maybe Abzan Charm.

I am liking this and my old constellation deck - it would be sick for a hybrid of both. the one i used was Abzan colors but I have a U/W control version as well.If you wanted you could try to use Heliod, God of the Sun and Skybind to get the same effects because it would just be stupid - you can repeatedly flicker Siege Rhino to keep draining them or flicker Hornet Queen to get 3 more tokens. the thing is with heliod you pay 4 mana to get a 2/1 ENCHANTMENT creature token - so it triggers constellation and triggers Skybind at instant speed, allowing you to either flicker enemy creatures or flicker your own as stated before. you can even flicker your scry lands to re scry - and this would also play into the altar of the brood because flickering re triggers Altar. Im telling you it would all work together perfectly - if you just find room somehow for heliod and skybind you wont regret it..

http://tappedout.net/mtg-decks/azorius-uw-skybind-control/

hmm Skybind and Heliod seems promising but thats more expensive to cast than bouncing sabretooths. also, i might have trouble milling myself late game if i have eidolon of blossoms. i thought also pharika but same reason as the former.

as for downfalls, im thinking of removing a glare of heresy to 2 downfalls and 2 abzan charms in the sideboards...ill playtest it more...

I love the idea here. +1 from me for sure. I will have to make my own variant. :)

well in blue you have Dakra Mystic which has a similar effect to pyxis, I am actually working on a deck using that as control, might add Pyxis of Pandemonium as well thanks for the idea

True its more expensive to cast then the sabertooth bounce BUT you dont have to recast from your hand - and sabertooth is for enchantments, whereas Heliod is for regular creatures like Siege Rhino and Hornet Queen to repeatedly trigger the ETB effects - BUT skybind/heliod combo has the added bonus of controlling your enemies creatures for 4 mana at instant speed, and it triggers constellation at instant speed, and it can also kill enemy tokens by flickering. on top of all that it gives your Creatures Vigilance - which is no joke - a Siege Rhino or Doomwake Giant with vigilance is Nasty - PLUS with the addition of heliod and skybind, it would be easy to get 5 white Devo, thus making heliod an active 5/6 indestructible monster - im telling you, it is an extremely versatile combo. i know it would be tough to find room but just give it a shot because i think in the end you will really like it.

if you are worried about decking when adding heliod and skybind here are my suggestions to make room maindeck, be more efficient, AND prevent decking:

-1 Doomwake Giant-1 Banishing Light-1 Pyxis of Pandemonium-1 Temur Sabertooth-4 Nyx-Fleece Ram

+1 Whip of Erebos+2 Heliod, God of the Sun+2 Skybind+2 Hero's Downfall+1 Elspeth, Sun's Champion

i think if you try these changes it will make it more balanced and more competitive with the addition of removal mainboard and the heliod combo - it will be harder to deal with and more diverse (even more then it was already) with better options and protection against removal - PLUS its just super fun. just try it and if you dont like it change it back, no harm done.

I really don't see how this is a mill deck. It's just abzan constellation with a bit of mill included. But while mill decks actually use mill to win, this really doesn't.

I don't usually play Standard, but I notice that the AVG CMC is pretty high. It looks slow.

SpikedEggnog

hmm, looking on those suggested changes, it will increase my average casting cost of my spells which is not im aiming. Also, I will loose the rams who can prevent aggros to go through while milling them slowly. Still ill try to consider heliod-skybind combo somewhere in the deck.

FAMOUSWATERMELON

This deck is not totally a mill deck, although you have altar and pyxis to potentially to decked out. You have several ways to win, either with the rhinos, doomwake giant or elspeth.

So, even if you start the game with two Altar of the Broods in your hand, it will still take until like turn 15-20 to mill your opponent out. It seems like an incredibly weak win condition to dedicate 7 cards to. If you're going to try and make non-blue mill work, you might as well look into ways to abuse it... oh and some stuff to keep you alive (board wipes etc.). gl.

... Like at least some fetch lands and Invasive Species...

I dont just mill with altar, I use pyxis too. While charging with pyxis, I have my reliable enchantment creatures to hold the line. In case they boardwipe me, I have whip and or starfield to bring back my enchantments/creatures.

Also if i have pyxis in the battlefield, both of us are milling and it has greater chances of missing the cards that they need (such as boardwipes). My advantage on pyxis is when I flip it, I will get all the permanents in the battlefield unlike most decks that rely on spells.

Windswept Heath and Evolving Wilds are already here to take advantage of the altar as well as Temur Sabertooth shenanigans.

I see what you are doing... I just think the deck looks really slow; and that if you are going to have such a slow deck you might as well run more powerful late game cards [as I implied before your mill win cons are like turn 15+ win conditions at the earliest - Ugin is way stronger and takes up fewer spots].

In my experience, I rarely have problems late game. Elspeth finishes games, Doomwake Giants finish games, rhinos do too...I thought about ugin but it messes my permanents...

if yore not satisfied with wincons, what card/s do you suggest as a finisher....while it doesnt messes up with either altar or pyxis?

I ran a mono-red mill deck for a few months in the wake of DKT. Basically it was Kurkesh, Onakke Ancient + Grindclock with a bunch of removal, boardwipes, and other artifact triggers/token makers

interesting!

btw did my last FNM report. check it out!