Hello my name is Skredth and i will show you how i play Sejuani, how i build.

Before that, Sejuani is a tanky champ ( full tank ), a little support, your slows and your ultimate. great jungler and great ganker. Sejuani is also easy to play, not so hard to master.

Pros
. Great tank in teamfight
. Really good jungler
.Great support ( Slow )
. Good chaser ( Flash and Q )

Cons
.Not very strong early game
.No high damage

Frost (Passive) - Sejuani's basic attacks apply Frost, reducing enemy Movement Speed by 10% for 3 seconds.
Great passive, nerfing ashe with Frost Shot, combined with E. good good passive

Arctic Assault - Sejuani charges forward to deal magic damage and apply Frost to enemies. Sejuani stops upon colliding with an enemy champion.
Range: 700
Cost: 70 / 80 / 90 / 100 / 110 mana
Magic Damage: 60 / 90 / 130 / 170 / 210 (+0.4 per ability power)
Nice Q ability, used to chase enemy, to escape, to pass wall, what else?

Northern Winds - Sejuani summons an arctic storm around her which deals magic damage to nearby enemies every second. Damage is increased against enemies affected by Frost or Permafrost.
Cost: 40 mana
Cooldown: 10 second
Magic Damage per Second: 12 / 18 / 24 / 30 / 36 (+0.1 per ability power) (+1 / 1.25 / 1.5 / 1.75 / 2% of her maximum health)
Good ability of farming, jungling and teamfight.

Permafrost - Sejuani converts Frost on nearby enemies to Permafrost, dealing magic damage and increasing the Movement Speed reduction dramatically.
Cost: 55 mana
Cooldown: 11 seconds
Magic Damage: 60 / 110 / 160 / 210 / 260 (+0.5 per ability power)
New Movement Speed Reduction: 30 / 40 / 50 / 60 / 70 %
Frost + Permafrost? Slow twice? Well, enemy can't escape from you !

Glacial Prison (Ultimate) - Sejuani throws her weapon, stunning the first enemy champion hit. Nearby enemies are stunned for a shorter duration. All targets take magic damage and are affected by Frost.
Cost: 100 mana
Range: 1150
Cooldown: 150 / 130 / 110 seconds
Magic Damage: 150 / 250 / 350 (+0.8 per ability power)
Oh! My favorite skill ! A really good skill in teamfight, chasing enemy ( Flash + Q + Ult )
Glacial Prison have many useful points, your teammates will thanks you for scoring an ace !

Smite
Useful for jungle, for steal enemy buffs, dragon, baron ( if you're pro ) Blue buff and red buff. making them raging :p

Flash
Escape or chasin, flash serve you! Flash + Q + Ult and you catch him !, Q + Flash. Chase order and Escape order.

Others sumonners spells

Heal
Why not? good in early game, completely useless in late game ( if you rest 1 hp, maybe it will be useful ) Or escaping from Karthus !

Ignite
Ignite... Great sumonner spell, used to gank,to kill Tryndamere.

Cleanse
Cleanse? Yes you can! In late game, you're always the first who engage, they will use they're ability on you, cleanse removes all ! But you can remplace it by Quicksilver Sash

Exhaust
Exhaust, slow, slow, slow. Great sumonner spell for your teammates, + you're slow, i don't think the victim can run away? LeBlanc maybe

Greater Quintessence of Resilience
The reason i choose quintessence of resilience is because it's giving armor, good for gank, and for jungling

Greater Quintessence of Warding
Gives armor resist, helping teammates killing LeBlanc? no problem !

Greater Glyph of Warding
LeBlanc hates you now, it's time to make yourself more hateful !

Greater Seal of Resilience
Before buying thornmail, that's for you, Xin Zhao, Nocturne, Tryndamere. WHO WANNA DIE?

Greater Mark of Resilience
I don't need to say something with this runes :)

Greater Mark of Warding
Nothing else :p

I start with Cloth Armor and 5 Health Potion

Ninja Tabi will allows you to run faster, gains more armor and reduces damages from the non-turrets. 550 gold only !

Negatron Cloak
Gives you magic resist, go gank the lane who have AP champs !

Regrowth Pendant x2
Remember we're building Force of Nature, and you need Regrowth Pendant x2, jungling easier, gank easier.

Giant's Belt-
I see, you need health, buy Giant's Belt ! Buy Warmog later

Force of Nature
Kk, we have finished Force of Nature. You have lot of MR and lot of health regen.

Warmog's Armor
So, we finished Force of Nature, now let's do Warmog !

Guardian Angel
Dream of all tankers? MR, Armor and a revive every 5 minutes, Useful in teamfight.

Abyssal Scepter
MR, ability power, great item for Sejuani

Sunfire Cape
Burning and freezing? Omg. Health + Armor + Northern Winds x2 Hahaha?

Zhonya's Hourglass
And for the end, Zhonya ! AP + Armor + great active. Yay !

http://www.youtube.com/watch?v=0s4L0y-CnVI

Here's the Sejuani champion spotlight if you wanna see it

http://www.mobafire.com/league-of-legends/item-purchase-planner#&item=53-101

Hope you appreciate this build

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