updated guide 8/8/2011
this build will work extremely well for ranked. my ranked scores for orianna are 21 wins/4 losses with a k/d/a average of 6.4/1.4/10

@stevebroil although chalice is a viable item. it still strays away from orianna's core build. the mana regen runes and catalyst's mana regen is plenty to sustain a lane. if im still struggling, i will just purchase a couple mana potions. my objective is to try to get that rod of ages around the 15-20 minute mark.

although q has shorter cooldown and less mana cost, i still think W is stronger since it eats chunks of hp out of any nearby enemies during teamfights; thus putting your team in the advantage. i dont only use the W during lane phase, if my team is doing dragon for example, and we see the enemy team approaching i will W a chokepoint so that it will slow the enemy down long enough for us to finish up and escape with ease.

@Wickerman2 (edit in last post: i wrote Queue instead of Q [lol])

The chalice is basically to replace a dorans ring, as many players use boots, 3 dorans in laning phase i prefer to go boots, 2 dorans and chalice, making it much more valuable plus it is significantly cheaper than archangels and gives the required mana immediately rather than needing to be farmed.

When harassing in lane you want to do it as often as possible, spamming W pre Chalice/arch will leave you dry in no time, yes blue buff is useful but having both is even better and not to mention having a fiddle jungle or a nidalee/other ap in your game can sometimes restrict access to that buff and it isnt viable to rely on it. Q however is much cheaper and does alot of damage, tho W does more it is still sufficient as orianna is very strong in lane regardless, big hit Q's aswell can make it possible for you to zone your opponent easily, whereas if you're versing a mobile champion many can often dodge the W in time wasting alot of mana and if you did land the Q it isn't enough damage.

@steveobroil What you said is true, however even with 10% reduction in damage, the amount of damage dealt by Q is extremely insignificant where as the W is a constant number. I'd rather have the ball out to near them or behind the ranged minions in order to zone the enemy. Once they attempt to last hit their own minion, i can punish them with the W's damage while keeping my distance, rather than having to run back towards them and shoot the ball at them again (having to be in that range)--so the Q is more predictable whereas the W is less predictable. After punishing them with my W, i also have the opportunity to catch up with them and Q them so i will get more damage in. Also having the higher level slow will completely neutralize junglers from trying to kill you. ive had xin, nocturne, udyr,etc, try to gank me many times, but my high level slow will almost immobilize the gank attempt and i can get away safely.

As for the chalice idea, yes it is a nice option (i rarely ever get archangel anymore- due to the fact that i am consistently managing blue buff in a timely manner)-so mana is rarely an issue any more. The only problem with chalice is that i think the chalice it would be a waste of an inventory slot whereas the tears can be upgraded into an ap item. I try to make most, if not all of orianna's items somehow geared towards AP because her damage output is extremely valuable to teamfighting situations. however, i will test it out and see if its worth mentioning in the situational item section. thank you for the suggestion

@Wickerman2 Maxing Queue is necessary for the harass, although W does more damage, Q is a short cooldown and leaves W as an escape tool. Hiding behind minions won't do anything if you continue to use Q to harass as you will already have your ball behind the minions, and the % loss through minions doesn't make that much of a difference. Also i suggest building chalice on her rather than Arch as it gives better sustainability, saves alot of gold, gives good defense and is overall a good item on a champion that is mana starved.

@NiNjaBalla maxing Q first isnt all that great. remember that the damage your Q deals is reduced by a percentage for every creep is travels through. so if your opponent is smart, he/she will hide behind creeps to reduce the damage output. at least with W, the damage is consistent and it also slows them down allowing you to auto burst them down a few more hits. i covered most of the mid/late game advice in my "lane phasing" and "team fights" section, but i will revise it soon so it will be more specific

i usually try to keep a distance between my enemy and myself. i harass them by punishing them when they overextend. i throw q very slightly behind them and hit w. this will slow them down enough for you to land a couple auto attacks. i do this when they are close enough to my tower so that i can use it as protection. in mid lane, i throw the ball at side bushes before feeling comfortable to push the lane or harass. as far as mana issues, she should be able to handle blue buff at around level 7. i mentioned on how to effectively kill him in my "jungling" section. otherwise, i buy mana and health potions whenever i go back to base(buy wards if you feel like you cant handle ganks)

How do you harass with this build? With just one point in shield and attack you get rid of a lot of her lane shutout capability. If you're using dissonance to harass you have just gotten rid of her escape utility (assuming your summoner skills are on CD) and you're burning through mana as fast as possible. I do agree with tear however, as it synergizes well with her short CD moves. Early game this build will suffer a lot though, no mana regen and not mana pots.

she deals with low mana capacity issues earlier and mid game. her cooldowns are one of the shortest out of all the champions in the game. it's easy to max out the tear/archangel passive with her low cooldowns. with archangel you'll have over 3000 mana. the 3k mana will compliment archangel's passive which will also gradually increase your overall AP with rabadon. your mana capacity will be very high, allowing you to constantly use your spells during team fights.

Why on earth would you get Tear/Archangel's on her?