I reccomend going this way for items:

meki pendant/health pots > tear/lvl1 boots > fiendish codex/lvl2 boots > catalyst the protector > nasor's tooth > Rod of Ages> Archangel's Staff > Hextech > Rabadon's > Will of the Ancients(or hextech gunblade if your team doesn't need the aura, it has same spell vamp, 5 less AP, but MOAR DAMAGE to synergize with nashor's, MOAR lifesteal, and awesome active)

Im not trying to tell you how to build your build, but I am fairly certain this will help out your early, mid, and late game more. Rod of Ages gives a ton of mana, which works well with archangel's and gives more HP than ryali's. Catalyst really makes you more durable mid game. Otherwise is fairly good build GJ.

Love the nashor's tooth idea, but the rest of the build could use some fine tuning :/

Not a fan of this build but from what I can tell this looks alright and would work very well in game. +1

Not a fan of this build but from what I can tell this looks alright and would work very well in game. +1

Thank you very much for help :D

Great job! The build makes much more sense now, and the mastries are muhc better^^ Also loved the Alternative items u put^^

about the HP seals. U didn't understand me correctly! Im not saying that Flat HP is bad to get, I love Fortitude Quints. What I ment is, that Flat HP seals are just not good runes. They just dosent provide a lot of stats. Maybe u dont know this, so its good that u will, but some runes are better than others. Its like Arp are the best Marks without a doubt, 17 Arp holy ****. Now for seals, dodge and armor are the best, followed by stuff like HP per lvl and Mana regen per lvl, and only then comes flat HP. They just not good to get. If u need a more in depth explanation, go to searz runes tip guide. It's on the most recommended guides, 93% rating, picture of annie, ull find it.

So anyway, I wanana change my vote, but i cant. If its not a comment-vote, u cant unvote it(As far as I know, and im pretty sure its like that.)
If u wanna have this Comment-to-vote thingy, edit ur guide, and then in the right side, u will see a box that u can flag it, to force people to comment if they wanna vote.(only 20 first votes). It's a great way to avoide troll votes and stuff, and only like that people can delete their vote, by delete the message.

Anyway, great job on the guide, love the changes :)

Hi Leaguesdf, thanks for commenting my build, here's what I changed and what I left:
- I added Rod of Ages to my build. It's great item. The order of items wasn't picked by me carefully, in my case it's different each game. But you're right, survi item might be picked later.
- Of course, you can pick runes you like. Seals can give you AP/lv, HP/lv and many different things that might be useful. However, me and my friends use Greater Seals of Fortitude (or such Quintessences) and it gives good results. On Orianna I don't recommend to start with Doran's item so you won't pick additional 100 HP. But most champions will pick it so you shouldn't be worse.
- Even though Perseverence mastery is quite useless, I think it's better than 10% time spent dead reduction. Even in late-game when you must wait 60 seconds to respawn, you'll get additional 6 seconds, it isn't much time. Also, Perseverence gives some MP regen. I decided to leave it.
With the rest of masteries you're absolutely right. I though Expanded Mind will stack with AAS and Tear of the Goddess Passive but I was wrong. Those 4 points is spent better now.
- I personally never use Ignite on Orianna. But many people like this spell and I also see some situations during game when I could use it, so even though I don't recommend it, I included it.
- About skills: I maximize E first because I usually use it the same way as Q, I don't care about shield if not necessary. You can get similar results with Q > E > W and Q > W > E so I decided to include both orders.
- I added a few items which I sometimes use and they might be useful.

Will you change your vote now? ;)

I -1. I wanna explain why, so u can learn from it and consider some changes
First, I gotta say Nashor's Tooth is so awesome! I would have never thought about this item, but it synergies so well with the passive. Very nice and unique choice.
However, the rest of the build is a bit problematic

-Rylai's Crystal Scepter so early... U arent akali that need the slow so much, and u even got a built in slow!! So why u need it so early?? t makes no sense... early u should get either Rabadons, or Rod of Ages( which u didnt even memtion...). I personally dont like rylai's on her, but its a viable pick, just take it later.
-Flat HP selas suck, get HP Per lvl or mana regen per lvl.
-Masteries, lots of mistakes. Perseverence is useless. U probably did;nt understand what Epanded mind does. Its useless. It's only work on BASE MANA. its broken and stupid. U should get 3 in and 2 in
- Ignite is better for AP carries, to add to their burst damage. Exhuast better taken by your carry.
-Command: Dissonance should be maxed b4 command: protect. After all, Oriana is an AP carry and not a support, she needs to deal damage.
-Archangel's Staff is a bad item Only get this on extreamly mana hungry champions like Anivia or Karthous. I dont find Oriana to be that mana hungry, especially if u buy Nashor's Tooth.
- U dont show any alternative items. Add items like Rod of AGes, Bashee's, Guardian angle as situational items.
So i hope i expalined to u what i think should be improved, and why I -1. Sry, ur guide is good, but needs work!! Good luck :)

Sweet but Simple, Nice! UPvoted.