http://www.newsarama.com/32328-detective-comics-writer-promises-changes-to-team-in-2017-and-more-tim-drake.html

This is the part that got me excited the most:

"What is the real League of Shadows? If the League of Assassins is the more obvious branch of Ra's Al Ghul's operations, is there a shadow branch? Is there something darker underneath?

We're going to see the League of Shadows' ties to Ra's Al Ghul and the League of Assassins, but it has definitely become its own entity. And how it operates is really, really, deeply terrifying.

It's all rooted in secrets, so I can't talk about too much, because I think you're going to see it all play out. But the philosophy behind them is really deeply terrifying. Their leader, I think, is one of the best adversaries in the Batman mythos, and I am extremely excited to bring them back into the fold."

So, the League Of Shadows will finally become cannon! and it will be a secret organization operating within the "standard" League Of Assassins, but while being even more dangerous and darker? it can't get more awesome than this! man, i'm so hyped for this!!

Who else is hyped as well?

I'm not sure how there can be Shadow branch of an organization that operates from the shadows already, they're the League of Assassins pretty sure they dont dance in broad day light before killing their victim. The Demon is the collective name of Ra's al Ghul's enterprise with Ra's himself being the head and the LOA being the fang. Silly explanation from Tynion really.

I'm curious to know who'll be actually in it, in that interview Tynion said that he thinks that the leader is one of the best Batman villains(meaning that villain doesn't enjoy such a status among fans and writers). He called the leader "them" which I think is an attempt to hide the fact that it's a woman. Stating it outright would narrow it down to Shiva, Talia, Nyssa and Cheshire and since it's a Cass arc Shiva is therefore a lock.

Other than that he's used Bronze Tiger, Cheshire, Ra's and Talia in the past, all extremely unlikely to appear in this story excluding cameos due to other books. Chances of his own characters Rictus and Graystone are high. Bane and Deathstroke are out automatically due to King and Priest's books. I suspect Merlyn will make his debut in Green Arrow in January so he's likely also out.So it'll probably be Shiva, Tynions own characters and maybe some characters from Cassandra's old series like Alpha, Mad Dog, Shrike etc.

Kinda underwhelming, though ofcourse it's all speculation on my part.

@entropy_aegis: Maybe The Sensei will make a comeback, a long time ago he was part of the League of Assassins (Before becoming Ra's father). He had a vastly different methodology than Ra's because he wanted to make assassination an art form and he was far more concern with skill than any of the other things that Ra's actually cares about. Since fighting was all he cared about, you could write a story with him a Cass being involved. And he certainly is not considered one of the best Batman villains.

Oh yeah, cant believe I forgot about him. Though Tynion actually did confirm Shiva in an interview some time back IIRC.

Well If he doesn't want to make Shiva the master mind, she could be the one that brings Cass into the Sensei's attention. One of the things that the Sensei liked to do, was watching fights between the most skilled individuals, and since Shiva's objective is fighting the most skilled of fighters, their team up is actually quite natural I am suprised that no one has made a team up between them.

Very possible, even probably tbh. Batman's team will be quite powerful by the time this story rolls around so hopefully we dont get so see Batman job to Kitty Kumbata or something, if that happens I'll riot.

@entropy_aegis: Lady Shiva will most likely appear, for several reasons 1) if she's still Cassandra's mother and toke a role on her upbringging 2) Lady Shiva is always connected in some way to the LOA and being that the LOS is a organization operating within the LOA Shiva appearing is by default likely and so is other famous LOA members...but that doesn't mean that either of them will necessarily be the leader that Tynion spoke of, actually it makes more sense that its someone more "Ras All Ghul-like" with the planing and all, Lady-Shiva type of characers aren't the most common for leadership-status, i'm not sure who that person would be, but i like what @black_arrow said, The Sensei working with Lady Shiva sounds cool and badass and it makes perfect sense, maybe Shiva and Cass will start as enemies and then join forces against The Sensei, and then Shiva gets killed and Cass seeing her mother dying loses her morals and punches Sensei's head out of his shoulders...in the end its revealed that Shiva only passed out and she was still alive...not bad of a plot :) just joking ;)

Idk about Batman jobbing, or even fighting the main villain for this, its a Cass-centric-story, so Batman fighting The Sensei or Shiva makes little sense, if they want to job someone there's better candidates than Batman, although i wouldn't consider losing to either Shiva or Sensei as "jobbing" since that the last time that they fought Batman needed the Suit Of Sorrows to even compete with The Sensei, and Shiva is considered to be the best fighter in the world...even story-wise it doesn't make sense, unless they severly hurt Batman then i can see Cass losing her cool.

We could also see a team-up of Cass and Bruce vs Shiva and Sensei...although it will most likely be the entire team vs the LOS...but what i most waitting to find out, is how they will explain the whole Mother-David Cain story, into Shiva having a child with David...i mean, don't you thinh that Shiva being Cassandra's mother and the LOS having plans for her (i'm betting that they do) is important information? that should have been adressed on Batman & Robin Eternal? i mean, are you telling me that The Mother who controls important people everywhere didn't knew about the LOS? please...i hope thats well explained.

Maybe he is using one of the League members who is not a martial arts guy, like Ebenezer Darrk, Professor Ojo or Doctor Moon.

Probably, yes, Shiva would be awesone for several reasons, and she's likely to appear in the story anyways, but when i think about "a leader" of sorts, i think on a Bruce Wayne, a Tim Drake, a Ra's All Ghul, a Pinguim, you know? Lady Shiva is more the type of "last toughest obstactle that you have to get past to" in a fight, than the person that came up with the plan...and with that being said, i don't mean that she's dumb or anything like that, because she's really not, but idk she's not "leader-like" to me.