I hope you like my way to build Sejuani, The winter's Wrath. Please every kind of help will be received to make a better guide. Thank you! This is my first guide so be compreensive please :3!

Pros:
-Great dfense abilities.
-Strong agains mages early game.
-Decent farming.
-Great ulti.
-Slow abilities.
-She ride a pig.

Cons:
-Bad jungling guide.
-Weak agains champion like Master Yi and Olaf.
-Bad armor early game.
-Cleanse is your principal enemy.

My Runes are very basic to a Tank, i'm not so creative in my runes:
TIP!BUY RUNES ONLY ON LEVEL 20 TO 30, BEFORE IT IS ONLY A WAST OF IP TOUGH



Marks of Resilence: These runes works on every tank. The armor bonus help you to defend your teammates from de carries.
Seal of Warding: I think Sejuani have very good techniques against a mage, so these warding runes are perfect to she.
Glyphs of Warding: The same reason to the seals. WHY NOT QUINTS OF WARDING AND GLYPHS OF RESILENCE? 'Cause the glyphs are the MOST IMPORTANT FRIEND TO A TANK.
Quints of Resilence: Your armor early game is very bad whit this build, but the quints fixed it a little bit.

My masteries are 0/21/9, focusing on disabling an enemy whitout die in the fight. The utility tree is not important in early game, it is most important in late game when you start to invade the enemy jungle. The defense tree just empower your abilities like a tank, and I like to do a complete defense Masteries (whit armor, magic resist, health, health regen, etc.)

Early Items:



YOUR PRINCIPAL WORK EARLY GAME IS DISABLE THE AP ENEMIES! I think the best option to have a good victory is to arrase the mages, that's because if they trapped you, all the team fall to you. Remember than the mages have very powerful nukes (the great part of the mages have almost one), so if the mage can't do his work (trap your team whit his spells), the team start to go alone and take wrong decisions. If you see in your lane is most powerfull the attack damage than the magic damage, just change Mercury Treas by a Ninja Tabi, and buy Frozen Heart before the Shurelya's Reverie.

Mid Items:


In mid game your work is HELP YOUR TEAMMATES to get the kill and turrets, and get the buffs of the jungle (BLUE for your MAGE and RED for your CARRY... don't forget it!), so you need a good health regen; whit a good health regen you don't need to come back so many times to the base after a teamfight. At these time the team start to fight more strong, so you need a Shurelya's Reverie: WHY NOT A ELEISA'S MIRACLE? Obvious: The Eleisa's Miracle gives you 25 health regen, 20 mana regen and 35 tenacity (the tenacity is not necesary whit your Mercury Tread) and your Shurelya's Reverie gives you a great active abilitie, 330 health, 30 health regen, 15 mana regen and 15% CDR (Cooldown Reduction).

Late Items:


Your work late game is DON'T DIE AND PROTECT YOUR TEAMMATES! If you're losing, YOU are the guardian of the nexus cause YOU are the tank, so you're very important. If you're wining, you're important to TANK THE TURRETS, 'cause KILLS DON'T WON GAMES, PUSH AND TANK TURRETS YES.

Another Useful Items:


These items are good too, but i think the items who I selected on this build work better whit Sejuani.
Specific Items (Thornmail and Sunfire Cape): These items also work whit Sejuani, but remember than your work is PROTECT AND DON'T DIE! Thornmail is a great defense if you're being attacked and Sunfire Cape is very usefull, but you have your Northern Winds and you don't need to be attacked to protect your team. Personally i don't like these two on Sejuani 'cause she is amazing!

First Artic Assault. Why? Because it gives you a great early attack to scout into the bushes and escape, then Permafrost to a good combo abilities, third Northern Winds to harras minions. Then at level 6 you won THE BEST TEAMFIGHT HELP EVER, your Glacial Prison: If you use it correctly. it's very destructive, cause this abilitie stun more than one enemy champion, and whit it you can prevent a gank, a teamfight whit less champion (Ex: 5 vs 3) or save an allied who is escaping.

REMEMBER: TO DISABLE AN ENEMY CHAMPION!



WHY FIRST PERMAFROST AND THEN NORTHERN WINDS? To prevent an escape or a Flash and then you can trap they into your Northern Winds.

THE BEST OPTIONS:


Teleport and Flash
Teleport: Esencial to a tank who needs to PROTECT THE ALLIES AND TURRETS. It gives you the greatest velocity to protect.
Flash: If you try to start or finish a teamfight, and see you trapped on the enemy team, just flashed away from they and use Artic Assault on a weak wall: Result: You escape. (If they still following you, take your ulti and trap they, AND ESCAPE TO RECALL)

Another good summoner Spells:

Exhaust: Most agressive, but not the best option to a tank... let it to your fighters and carries.Ignite: Good to ultimate your enemies, but it work best on a mage.
Heal andClarity: Very usefull, but is most for a supporter than a tank.
Ghost: Perfect to escape or run to save an allied, but it work best on a ranged.
Cleanse: To clear disables on you, but Sejuani can escape whit flash and Artic Asault, just she don't need it.


JUST NO:


REMEMBER: YOU'RE NOT SUPPORTER. YOU'RE NOT JUNGLING IN THESE GUIDE. YOU'RE NOT PUSHING AND YOU DON'T NEED TO LEAVE A LOT OF TIMES. Just don't use it in these guide.

Just tips:
-Your abilities are you team friend.
-Help your friend to take the kill, you don't need it.
-Save al the lifes you can.
-Protect all the point, don't forget anyone.
-Pay specail attention to the junglers and the mid lane.
-Don't try to gank, let it to the junglers adn champions whit more attack than you.
-THANKS FOR READ AND PLEASE COMMENT!