After playing alot of games with Orianna I found her one of the strongest AP carries in the game. But seeing so many players simply not optimizing her damage and supportive skills, or simply failing to play her decently I decided to write this guide.

The Runes I use are standard mage runes.

Greater Mark of Magic Penetration x9 on Red for extra damage on all your attacks

Greater Seal of Scaling Mana Regeneration x9 on Yellow to make sure you don't run out of mana as fast and alow you to stay in lane

Greater Glyph of Scaling Ability Power x9 on Blue for extra damage and more shielding

Greater Quintessence of Ability Power x3 also for extra damage and shielding

At level 1 I start out with a Doran's Ring, giving me the essential mp5, some nice ap and hp.

I try to stay in lane until I have farmed at least 825 gold so I can buy Boots and a second Doran's Ring,
I would not recommend to skip the second Doran's Ring for it will give some extra mp5 that allows you to stay in lane without running out of mana.

The next thing u want to do is upgrade your Boots into Sorcerer's Shoes giving you the 20 magic pen that will allow you to start dealing good damage. Do NEVER buy the by default recommended Ionian Boots of Lucidity since Orianna doesn't have any need of cdr because her main abilities already have very low cooldowns

After upgrading your boots you will rush Rabadon's Deathcap for it is by far the strongest mage item in the game, not rushing this item in favor for items that give mp5 or defense is dumb because Orianna doesn't need a lot of defense for she can be extremely effective at large range and if played properly she won't need any more mp5 either.

Now that we have our basic build finished there are a few items I would recommend to build, although the order of building them is dependent on who you are playing against and how well the game is progressing.

- Void Staff: build this item if everything is going good and you are winning the game, simply ignoring 40% of enemy magic resistance is quite a lot of extra damage and will make items like Force of Nature and Banshee's Veil less effective against Orianna

- Zhonya's Hourglass: get one of these if the enemy team is heavy on AD champions that either have range or a reliable dash to get close to you. I recommend this item over heavy armor items because the 100 ap is gonna help out alot and if you position yourself well you should not take to much damage anyway. Besides this item has a great active that can be used not only to save yourself when you are focused in teamfights, but also to dodge attacks like: Requiem, Enchanted Crystal Arrow and Paranoia if timed correctly.

- Abyssal Mask: build this item if the enemy team is heavy on AP champions. It has the highest amount of magic resistance in the game and also offers some extra AP and punishes your enemies for getting close to you for they will lose 20 magic resistance leaving them extra vulnerable to your attacks.