How do you beat an AD Sion, He just dropped me to half health with 1 stun/Attack combo

I have Armor/MR Runes Arp runes and working on new quints atm

Hes a rough lane how do you beat it?

Well you dont really engage him until maybe you get a little more built, utilize your farming abilities to get ahead of him, especially if your solo top. Start with a vamperic sceptar and just last hit away with your Q, and auto-attack with your superior lifesteal if you need it

And then you ignore everything the last person said.

Vamp scepter? Lol, he must be trolling.

Runes are fine, MR,Armor ARP, i'd probably get Phys damage runes but im lazy about last hitting.

Get your cloth 5, don't do vamp scepter lol, it takes 4 seconds between the time he activates it until he can burst it, so destroy it before then and you won't take damage, if he's going AD then his shield won't ever get too high of HP to break it, and his stun wont deal too much damage because he isnt leveling it.

If he activates it and waits to run in, just back off for the remaining 5-6 seconds, he'll blow up on the minions and you can auto attack them to restore any health you are missing(dont get hit by the explosion) and then be aggressive on him.

This is a really old thread but came up while I was googling it.
I will think this is a top AD sion vs top irelia.

As an Irelia, you have a massive advantage vs sion early game pre-6. Make him cry with your Hitan Style. If he goes AD, his enrage will cost him 6/8/10 health per attack whereas you will Gain 10/14/18 health per attack. With a simple calculation, 16/22/28 health will go IN YOUR FAVOR if you both attack eachother outright! Start with cloth5 into tabi and trade as much as you can with him.

As Sion, he has no escape mech other than his stun. You're Irelia. The stun duration is decreased with your passive and if your jungler is nice enough to gank with red buff, he's good as dead.

Post 6 requires a bit of an unconventional build due to his insane lifesteal and attack speed from his ult. Every time you engage, he will ult and out lifesteal/damage you. This is what makes AD sion viable, and what makes AD sion scary as hell. See his ult? People run. You can easily negate his ult through the purchase of an executioner's calling. 1460 gold with a grievous wound active every 20 secionds??? TAKE THE DAMN ITEM! You will make AD sion cry every single fight in your lane!!!
Take precaution by making sure you have a solid tabi as well as phage to peel if the fight is going against your favor (the phage also helps to chase him down).

Late game, if the sion is not already 1/10/0 or 0/10/1, take a GA and Banshee's to further negate his stun and dive his carries.

Do not forget to use your grievous wound active lategame. Put it on sion, and he'll die instantly. Ignite their carries and take care of the carries while the Sion dies to your team's CC. If he survives the 8 second grievous wound, wait 12 seconds and tack it on him again.