So, Boar Bi- ... er, lady! Commonly regarded as completely subpar in every way on SR, and pretty much the same on Dominion until so far in late game she's probably already sunk her team.

I'm having fairly good results with her now that there's reasonable upgrade paths for the items that form her early game core (and that will actually do something late-game, minus Shroud -> FH). She was servicable before (and probably last patch even, TBH), but she was trapped within such a rigid item build to both do damage and not explode; if early game didn't go spectacularly you were a gigantic anchor until you managed to hit your CDR/MPen stride outside of landing amazing ultimates. Line of the day: TRIPLE KILL! -> "Sej isn't supposed to DO that much damage!"

Build so far:

R -> W -> Q (low charge CD = GODSEND) -> E (IBG slow renders the slow boost moot )

4/25/1. If only I could reach Arcane Knowledge, RIOT.

Boots - Kindlegem - 2/1 pot start
Guise
Sorc Boots (or Merc if there's an inordinate amount of CC) - upgrade with Alacrity if mobility becomes a problem or if I base without the gold to get anything else than an amp tome.
Negatron & Vest
BFT
Shroud
Sheen
Iceborn Gauntlet (125% Sheen and Phage AoE proc + Shroud for those of you unaware, and it has a blue proc so it's obviously better.)
Abyssal or Wooglet's: Do I need MR or do I have so much gold that I don't know what to do with it? She ends up with enough AP that Wooglet's actually makes quite the bump in her AP (now if only her ratios reflected that at a glance instead of having to actually think about her W.)
Sweeper if not before; grab as early as needed to deal with pesky Vayne or Wukongs (the latter of which is now back to being in almost every frickin' game). Also useful in general if you're the only one with a sweeper and you need to use it for recon and bushwhacking purposes.
Rylai's

She's always been able to do great DPS with her W, but her burst is surprising if you can get an ultimate into charge and IBG proc - I took down an Ezreal within the second after my stun wore off. After playing Irelia/Eve/Kayle/Akali for so long it's actually refreshing to have to use brain and actually think about skill shots, especially how her's work; sure, you can hit an entire group with either ability's splash, but it actually matters who you hit directly (Would you rather be hitting the carry or giving Leona a hug; would you rather stun for two or three seconds?).

Anyone else enjoying pig lady?

Why start kindlegem? Weak start for top skirmish. I prefer boots and 2 ruby crystals.

What's keeping you from getting arcane knowledge in masteries? Is the one point in utility (revive mastery, i'm guessing) really that necessary? With the way that % magic pen is calculated after flat, I'd think the 8% is more worth it, especially if you pick up a void staff as your last item like I do.

Shroud into FH is a better defensive option than Gauntlet. The spellblade proc doesn't do much if you don't have armor pen. And if you're building rylais anyway, do you really need another slow?

BFT op. I actually rush that and will as long as it continues to be overpowered.

Why buy wooglets if you just said that her ratios are bad? And with the armor changes and so many black cleavers/last whispers around, it's better to just get some more health.

@Kindlegem:

Edit: Logic sez: 10% CDR for level 1 abilities instead of 140 HP is a dumbass idea. Stop being so godawful, me.

@Revive Mastery: The health boost is worth it as far as I'm concerned; I have enough flat penetration to murder the squishies sitting in the back and although Sej can skirmish with tanks late-game if built specifically for that, it's not really her specialty or even all that efficient. If people are stacking MR to counter Sejuani then that game is either going ludicrously and exclusively in your favour or you've already won once Pantheon spears start boring holes through people.

I don't bother with void staff. My primary role isn't damage and I'm not willing to drop more slots than I already am on pure damage (Sorc & Torch). If I somehow become the primary damage dealer then clearly something odd has occurred.

FH: I'll use it when we need the -%AS or if I want to shift more to defense. So far, the damage boost has been preferable (I'm murdering carries, since when do they have any armor?) and the AoE blast compliments her kit.

I've yet to get to Rylai's before the game's over. I'll either grab a sunfire for that last minute boost for the last fight or don't get to the point where I upgrade it all the way up.

BFT indeed OP. It's my first finished item, but I find little point to rushing it when I explode into little pieces because I don't have any armor or MR in the meantime. I don't actually bother with a shroud, though, as I had listed. Edited above item build to reflect the reality that I usually go negatron/chain vest after guise to stop aforementioned exploding.

Wooglets: When I have so much gold I may as well get a luxury item. This situation means that I'm both doing ridiculously well (and somehow the game is still on) while I don't need an MR boost from Abyssal. While her AP ratios aren't fantastic, she's still got a 1.8 ratio per ability round or 2.6 with her ultimate tossed in, and that's all AoE (though not practically so on everyone unless they group nicely to get charged and permafrosted) so if going for raw damage, AP is still her best route. I've only had one game so far when Wooglet's was an option (and we got nowhere near that close to endgame) but it's still on the table.

I'm looking at your masteries a bit and I'm wondering what your typical end game armor and MR totals are, because legendary armor is pretty meh. at 300 BONUS armor/mr (which is closer to 350-400 in each respective trait with bases) you're only getting an additional 15. it's pretty awful and can be allocated elsewhere. Safeguard might even be a wise investment depending on your playstyle. reinforced armor can help deal with some of those nasty pantheons floating around right now.

I picked her up a few games with your suggestions; loving it! Personally, I try to build Glacial Shroud before I finish BFT so I can get my CDR to 29 from 14.

Back to hating Teemo. I've got spell-based DPS, I'm cool, right? Right?

Teemo Q -> Can't apply Frost -> Can't permafrost until charge is back up -> He shrooms and escapes charge range and dismantles my team in the six seconds it takes me to catch him.

/incoherent screaming

I shouldn't have Legendary Armor specced into. The mastery changes must not have saved from last time, hmm.

Logging in to fix that, thanks!

BFT's CDR and rather significant damage boost makes it worth finishing the torch first, imo. I'm not usually mana starved past the first fight since any time I'm out of mana I'm usually also out of health and need to base. Otherwise you're paying 825g for a slight armor boost and the CDR; you can pitch in 700 instead and just grab the torch. On the other hand, if you're put into a situation where you need FH, I'd grab that before grabbing torch because the safety is going to take priority over the damage boost.

Armor options will seem more appealing once That Which Must Not Be Spoken Of has been removed.

Look on the bright side; he spent his Q on you rather than your possibly squishier AA-reliant teammates. Your own Q would still apply frost, right?

I'll try going directly to BFT a few times. Again, thanks for rekindling Boar Love.

Actually, Sejuani has already been mostly acknowledged as viable by the competitive Dominion community already, seeing as how she has been used by both of the top teams in the weekly DominateDominion tourney.

I find her very strong from early mid game

Once you itemized your first CDR item, your Q will be very useful and the permaslow + Blackfire torch thing does do a lot of damage. From there on, just stack HP AP items much like amumu would

I like the boar! I tend to rush a Sunfire, then go for BFT and other CDR items.