I never really played sion until my team got raped by one. You have a **** ton of spell damage and a good amount of life. You have a stun, a shield, and lifesteal. Wtf else do you need? Oh wait, mobility. Thats what ghost and flash are for. Lane against a squishy, you might as well call gg.


Summoner spells:
You really need some mobility to get people in range of your stun, so ghost and flash are the best options. You can also go for exhaust if you want. If you don't know how to be smart with your mana, grab clarity. You shouldn't need any other spells.



Item build:
Grab a doran's ring to start off with. That along with your runes and masteries should give you a decent amount of mana regen. The ability power and life are great too. If you can't manage your mana well, grab a mana pot instead of a health pot, but remember, you don't have any health regen.

Next, go ahead and grab sorcerers shoes so you can get close enough to stun people. Other boots with this build aren't good options

Go ahead and get a mejai's so you can start getting stacks. If you aren't doing well or its a slow game, it's probably not a good idea to get one though. Just skip it.
Sheen doesn't do too much early game, but it gives you some much needed mana and some AP. The passive isn't all that great except it helps a little bit in combination with your ult.

Zonya's is a no brainer. I'm not gonna bother explaining it.

Lich bane's passive adds a lot more burst damage, especially if you're fed.

If you're up against a team with a lot of magic resist, grab void staff earlier than now. Otherwise, its a great late game item that gives pure AP and magic pen.

At this point, you have a lot of life and AP and you're either getting focused a lot or not dying if you're smart enough. Get guardian's for some survivability and to make sure you really don't ever die. Other options are hextech gunblade or abyssal scepter. Its up to you.



Skills:
Feel no pain (passive): Great against attack speed champions. Combined with enrage, it makes you pretty tanky.

Cryptic gaze is great because it stuns for 2 seconds no matter what level it is. It also does a pretty good amount of damage. The only problem is that it's costly. DO NOT HARASS WITH THIS ABILITY. You're run out of mana way too fast. The only reason you should use this to harass is if you're going to hit someone with your shield right after you stun them. Also use this to help your teammates get away if they're being chased.

Death's caress is your bread and butter. It's your main harass tool and your greatest amount of damage. In team fights, make sure it's up whenever possible, even if it'll get popped, because if it does, it means you're taking a lot of damage anyway. But don't forget if it gets popped, it doesn't do any damage. For harassing, it's best to wait in the bushes until it's ready then run out and hit someone. It's really good for clearing minion waves too. By midgame, you can clear whole waves with one shield. Combined with enrage, you gain a **** ton of life when you do this. Also, your shield is really good at counteracting ignites/poisons/dots (like morde's ult) and from keeping you alive if you're being chased.

Enrage really isn't useful early game when you aren't killing too many minions and you don't do much attack damage anyway. It does help with your ult though. Go ahead and grab it around 7 unless you're solo laning, then get it around 5.

Cannibalism: Great for healing yourself and your teammates. It has a decently short cooldown too. Don't be afraid to use it for jungling if you're low on health. Like I said earlier, it's better to have it up when your sheen/lich bane procs.


Strategy

Solo laning: If you're solo laning, get your shield first instead of your stun so you can harass more and be harassed less. Also get enrage earlier than you normally would because you'll be getting a lot more minion kills. If you're laning against two heavy champs that have a lot of health or against a healing champ, you probably won't get many kills. Be more cautious than you normally would. If you have a squishy champ in your lane, you're in luck. Harass with your shield and finish them off with stun/shield. Don't forget to call over your jungler to help gang someone every now and then.

Early game with a partner:
You really want to lane with a burst damage champion. Champions with stuns/slows are good too. Make sure you get your items quick and head to the second bush. If you're with a good partner and you have a squishy champ in your lane, you'll almost always get first blood. Keep harassing with your shield. Once you get a couple levels in your shield, you can turret dive if they're low enough. Your shield can absorb at least one turret shot early game so run in, ghost/flash if you have to, stun, and blast em with your shield (make sure its ready before you go in) and get out. If you're gonna have to stay and fight with em for a few seconds, or if they have snares/stuns/blinks then its probably not a good idea, but if you think you can stun them before they get any of those off, which I do a lot, then go ahead. If your lane partner is gonna help you, make sure you have turret aggro if they're squishy.

Mid game:
First off, towards the end of early game and beginning of mid game, you can go gank middle if they overextend and/or have low health and you have enough time to do it. It really helps if you ghost or flash in to make sure you get your stun off, and make sure your shield is ready. Go ahead and pop your ult too for good measure. Don't run straight towards them though, run diagonally ahead of them so you can get your stun off. By this point you should also be grabbing golem buff whenever you can. Don't use your stun on the golem unless you have a lot of mana, just use your shield and ult. Don't use your ult right away either, just to make sure you're at full health when you finish. Don't be afraid to go gank the other lane either. Sion is really good at ganking, especially with the help of other players. Just make sure they don't pop your shield. Also, if you see enemy minion waves building up, go blow your load on em. This helps you gain a lot of life and money in a short amount of time.

Late game:
By now you should be pretty disgusting, but don't get carried away. Dont go diving into the middle of the other team and think you're gonna live. You really don't have much armor or magic resist and you'll get burned down pretty quick. The best thing to do is wait until the fight is initiated and run in when your shield is ready to blow. Make sure to stun their carries/healer(s). Don't forget about your zonya's. You can use it if you're being focused, to make sure your shield doesn't get popped, or to buy time until your shield or stun are up. If you're about to die, you can use it to flash out and have your shield up so you can get away. Don't be afraid to turn on someone that's chasing you if they have lowish health either if your stun is up and your shield is ready to blow.



Proof:
If someone could tell me how you add the boxes with your game summary in it I'd appreciate it.

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