Disclaimer:

I am building Sejuani as a tank. The express purpose of a tank is to initiate, perpetually slow everyone, and refuse to die. All damage is supplemental and for educational purposes. If you 1v1 with this build, you do so at your own risk. The author takes no responsibility for damage resulting from playing a tank build like a tanky DPS.

Endurance training! Says so in the bio. I LOLed. You have to give them credit for trying, anyway.

Anyway, this build is kind of funny because the final items are all somewhat thematically linked to the character. That's how I'm building at the moment, at least.

Philosopher's Stone First, Philosopher's Stone, Boots, and Heart of Gold to get started. I don't take better boots any sooner than this unless there's a special reason.

Glacial Shroud is next. Frozen Heart has great synergy with Sejuani's kit, slowing down AS where her kit slows down move speed. Together, it is a drain on enemy auto-attacker power. If your enemies don't have strong auto-attackers, though, try another build.

Then you can go for Mercury's Treads, though you might prefer others. It's usually enough MR to tide you over, so I take it, but Boots of Swiftness is tempting.

Next is Warmog's Armor. Of course the health scaling isn't *that* great on Northern Winds, but tanks get tankier with health, not with AP. I'd rather do my job and get free damage on the side than spend directly on AP and barely have it pay off. With no free resists ( Leona, Rammus) or health buffs ( Cho'Gath), you have to spend a lot on raw stats just to be tanky enough, and it doesn't get much tankier than Warmog's.

Force of Nature... That's kind of what she's all about, isn't it? Move speed, MR, regen... not much not to like. Negatron Cloak may sometimes be taken earlier than here as needed. But lately I've come to like Banshee's Veil more, for the bubble and for the health. If you really need the MR, Force of Nature is still there. Or you can even take both, getting rid of one of the later items if needed. The best thing about taking BV at this stage, though, is that your damage doesn't trail off as rapidly.

Arctic endurance training will lead to this, literally and figuratively. If you really don't need the aura, then you'll want to try a totally different build. As it's CDR and armor, it's a bit unique and hard to replace with a single item. You can leave the shroud as is if you're up against AD champs who don't really need AS, like Riven or Renekton.

Because what else are you going to do with 4k+ health? I used to put this at the very end. It's up to you. If you're doing well, this is a good place for it. If you're having a hard time just staying alive, don't take this too soon. (Unless the armor is badly needed more so than health). This can be taken before Frozen Heart, too, possibly.

Because Permafrost is only up about half the time, and the health is great. You can string on a couple more seconds of extra CC when they just don't quite want to die. It's debateable whether it's necessary to have a mallet. Alternatives follow.

Runners-up:

In place of Frozen Heart, with some other arrangement like Shurelya's Battlesong and/or Ionian Boots of Lucidity made for CDR. If you take both CDR sources, you can use some of your glyphs for MR instead. This can also replace Warmog's Armor, but Frozen Heart already grants a lot of armor and you might not want both, usually. 1250 health or so from Warmog's is 25 damage/sec for Northern Winds, while the cape grants 35 and another 750 health -> 15 damage/sec. But if the enemy is mage-heavy, you'll value the health more than the armor or the aura. Your call, as it's a strong choice.

Your job will be to get up in their business, and you'll be spamming magic damage, including an AoE cloud, all scaling with AP. It doesn't scale that well, but your allies might like the aura. You can consider this instead of Force of Nature, or you can find a way to take both if you really need MR this game. Another important note is that many champs have base MR of 30, meaning that if they have no runes or items, you will be doing close to true damage with this item; the more MR they have, the less you will notice Abyssal Mask. If they're all glass cannons, this is a respectable counterpurchase.

If you're really good at using the active properly, this can be helpful. It can go with Shurelya's Battlesong for CDR, and you will be able to get rid of Frozen Mallet and Frozen Heart, which then would be a bit redundant. However, this means you won't have any CDR at all until you give up your GP10, and I don't like that much.

A little more burst damage here from QWER, but the health+AP is not as stong on Northern Winds as Warmog's Armor is on its own. This item is probably the strongest choice for overall burst damage. I don't think it's the best idea, but sometimes your team just can't quite finish the job all game, so it has to be you. But that one last sliver of health that gets shredded instead of remaining might end up being your own, so do what you will.

The "I don't think so, Tim" tier

Everything you do is AoE. The Arctic Assault -> Permafrost combo already does 70% AoE slow, so the extra 15% isn't that great (counted at half effectivness, for a 7.5% slow... this multiplies out to a 70.75% slow, seriously). Sure there's AP, but I'd rather be a tank. This is sort of respectable because at least it's not a Deathcap or anything. But I think it's not worth it. Basically it'd only be good for slowing with Northern Winds, but I like to proc that alongside Permafrost anyway.

Considering how well her skills combo, there just isn't enough Sheen damage to go around. The other stuff is sort of tempting maybe, but not that tempting. Zeal is attractive-ish and helps with Atma's Impaler, but to me, at best that sounds like an option for a sixth item, with the understanding that the game's almost over.

Probably MPen marks, maybe AS. Your call. AS might not be used to the fullest in most games, as Atma's is a sixth item throwaway. But you might be able to jungle better with a bit of AS.

%health seals, for sure. Enough resistances will come from items, and Northern Winds encourages you to err on the side of extra health.

CDR/level glyphs because 8% from masteries and 20% from Frozen Heart leaves a little more than you can do with glyphs, getting you close to the maximum.

Movement quints and %health are strong options. Your call again.

Ghost is really helpful, since your job is to stay close to enemies a lot. Flash shouldn't really be necessary, given the long range on your dash, Arctic Assault. If you need to get away and you wasted your dash already, then you probably made an error of judgment going in. Other than that, the only time you can't dash out is if another enemy champ is right in your only escape route. So try to avoid that, and it'll be ok.

Because you don't have enough CC already. But seriously, I get it a lot. It's just that good.

1/21/8

Sorry, I did it like Phreak, and I know that's unfashionable or something. But resistances, health, movement, CDR, and gold are all available in a 1/21/8 setup, as well as both enhanced summoner spells.

You can also try 9/21/0, since with runes and Frozen Heart, this will put you right at 40% CDR and you'll get nifty MPen.

Seems pretty straightforward to play, actually...

* Don't waste your dash if you might need it to escape is the first thing. If you don't have the upper hand, then dashing in could be a bad idea.

* Note that Northern Winds does more damage if frost is applied, and Permafrost doesn't affect unfrosted targets. Auto-attacks apply frost, or Arctic Assault to splash at the end of the dash or at your first champ collision. So if you have several targets, you can indeed lead with your dash, following with your W and E. But only if it's safe.

* About that ult... Your call. If you've been playing for long, you should have enough of a general idea of when to ult, and this champ's ult isn't so unique as to be mind-bending or anything. It should already feel familiar. As it is with anyone else, it's pointless to harass with your ult if it's just going to be a damage trade that doesn't go anywhere. Something really interesting should be going on, like you have enough to finish it, or you have to stop them. Initiating a teamfight is one use as well, but usually you'll want to wait for a decent shot on two or more targets, or a really good shot on one squishy target.

* You're a tank. A little AP is ok, but the cooldowns are longish and the scalings don't add up to enough. You can experiment with Rod of Ages or even Rylai's Crystal Scepter if you want, but I think damage that comes from tank stats is better.

* If you're a bad jungle player like me, you can gain a few levels in lane before jungling. It's a lot less frustrating that way, and I hate having Smite take up a spell slot anyway.

* About that jungle - note that W and E require permafrost, so for the wraiths, I like to dash in, hit W and E, and attack the big one. They all generally die around the same time. If you need a second Northern Winds, you can auto-attack the smaller ones once each to get Frost on them again.

* Experiment with the dash. Sometimes you can jump over walls. This can save your life, or it can get an enemy locked up in a dangerous place.

This build goes for about 4k health and well over 100 of each resistance, granting Northern Winds 80 bonus damage per second (a bit more, actually). Meanwhile, you're CCing everyone all the time and hopefully they're having a hard time killing you.

Pros

* One of the easier tanks to play
* Long-range dash, one of the longest in the game
* Slowslowslowslowslow stun slowslowslow
* Clears wraith camp particularly well, so you can swing by sometime and pick up a few gold occasionally
* Teamfight not wanting to start? Hit R. A lot of stuff will happen every time.
* 4k+ health with a full build (with this setup)

Cons

* No free tank stats
* Compared to other champs, not quite so much versatility seems to exist in her kit, despite its general team helpfulness. She can perma-slow and engage/disengage whenever she feels like it, and that's pretty much what she does.
* This build is unlikely to be completed in most games (but partial builds are fine for where they are)
* This is not a tanky DPS build. Health scaling is nice, but it's not AP, and the AD isn't really a ton and there's no Triforce (not that it would be good on her anyway, Sheen doesn't proc that well on her, I don't think). So don't go 1v1ing all over the place.

Ultimately, she doesn't seem OP or UP to me at the moment, so it's just a matter of whether you like the play style or not. I get the feeling that she's easy to play, but if there's anything hard about her, it's using the dash properly. (The ult is a skillshot too, granted, but it's as broad as a barn door and I've hit with it when I thought I'd miss before.)

Ok, that's how I build. Have fun.

If they're not expecting it, ulting and then jumping over a wall is fun. Basically, it's RQWE in rapid succession. If you can hit two of them with backup present, then that could easily be two kills.