Sion is as how I play him, an AD Tank. He has a decent CC from his Q, Cryptic Gaze (however it doesn't increase in how long it stuns as you level up), a Shield that can explode to deal some AoE and potentially save your life. But heres my favorite part about Sion. His E, Enrage gives you a flat 25/35/45/55/65 AD (while taking away health per attack so be careful early game, but also gives you hp per kill 1/1.5/2/2.5/3 doubled on champs and large monsters/minions) and his Ult is one of the most fearsome thing when dealing with Sion. 50/75/100% Lifesteal and a 50% boost to your Attack Speed. So you attack much faster and heal for a substantial amount. Not to mention it heals 25/37.5/50% of the damage you deal to those around you. Making you valuable in Team Fights.

For Sion, I would recommend Attack Speed, flat AD and Flat HP. The rest is up to you (gold gain is helpful as well, maybe not right away but that 5 gold per 10 seconds adds up in a 30 min game (about 900 so basically a free Vampiric Scepter or some health potions to offset his loss in HP from Enrage early game). Honestly this part isn't that important to me as say Masteries... speaking of which

Just check the Mastery page. This is to sustain Sion by boosting his damage to high amounts. And as such his teammates during teamfights

Gaze is always last to hit 5, Enrage hits 5 first, Shield is the 2nd to hit 5 and always get his Ult whenever you can.

Depending on how you play Sion he can either have large amounts of Mana but low sustain if you play AP (not to mention high damage from his Q and W) while if you are going AD as in this guide. You have obscene sustain, and chasing ability (especially through the Jungle). But low Mana early game which can really bite you in the keister later on.

So this is the end of the guide, granted this is my first guide on here so if you have any ideas how to improve it send what you think to kingk1132@gmail.com or just add me on league from my summoner name KGtheLPer. Have fun. And play how you see fit. And I forgot this in Items but, BUY RAVENOUS HYDRA FIRST. If you playing as an AD Sion this is THE most valuable item for your set. Since it applys ALL lifesteal effects to the damage you do. So if your in a wave of minions and your stuck in a 3v1, pop your ult and prepare for battle because your not dying anytime soon if you play right. This build does have a bit of a learning curve so, do your best. I know it took me a while to figure out this build and I am glad I have it now, my win rate while not as high as it could be has gotten substantially better, about a 75% chance to win if you communicate properly with your team.

Now get them to the Choppa