The Keeper of the Lake Elder primal

[Balipu]

It's the thuper thecwet one I wanna know! XD But my gils on Ishgards manipulating Ascian as part of the main scenario^^

Ehhh if you say so.

[Nestama]

It had fenrir last minute in it for no real reason.

And what a massive disappointment of a boss he was... easier than Anantaboga :/
As for Siren, she is a race in this game. Sure, she was a summon in previous Final Fantasy games (a boss in FFV, which our first encounter with her in XIV references somewhat), but she's a race in Greek mythology. The lamiae mobs could probably count as sirens themselves, if they knew how to 'Belly Dance'.

[VargasVermillion]

Re-sealing the primals might actually be an issue at the moment, the only reason garlemald has failed to conquer eorzea is mainly due to primal influence, with the ultima weapon gone that's even more true.

[Balipu]

Re-sealing the primals might actually be an issue at the moment, the only reason garlemald has failed to conquer eorzea is mainly due to primal influence, with the ultima weapon gone that's even more true.

Not to mention re-sealing the primals would rob us of a lot of content. No more trials

[lololink]

Not to mention re-sealing the primals would rob us of a lot of content. No more trials

Not really, we can still battle the primals even if you are the time of the storyline where they are trapped in Ultima, It could even be a lore explanation for EX primals, HM : hurry a primal is going wild, kill it! EX : Ok now we are ready, we trap him this time and seal him with the others we sealed already.

[Balipu]

Not really, we can still battle the primals even if you are the time of the storyline where they are trapped in Ultima, It could even be a lore explanation for EX primals, HM : hurry a primal is going wild, kill it! EX : Ok now we are ready, we trap him this time and seal him with the others we sealed already.

True, but I like the fact that currently there is a lore explanation to why you can kill the primals over and over again ten times every day. That would end if we sealed them in.

[Nalien]

We wont be sealing Primals, that simply wouldn't make sense with the upcoming planned content. While Free Company Primal summoning hasn't been a topic talked about by YoshiP a lot, the last time it was brought up he said they were waiting for it to make sense within the context of the story. If we seal them, it would only make sense if that seal fails almost instantly...

I find it more likely that "The Rejoining" mentioned in 2.4 as the subject matter behind the Isle of Val incident could likely change the rules on Primals and allow them to exist without draining the planet of Aether. Meaning they stop being such a major threat and allows us to summon them.

[Edellis]

We wont be sealing Primals, that simply wouldn't make sense with the upcoming planned content. While Free Company Primal summoning hasn't been a topic talked about by YoshiP a lot, the last time it was brought up he said they were waiting for it to make sense within the context of the story. If we seal them, it would only make sense if that seal fails almost instantly...

Something tells me the moment this is going to have something to do with Garlemald, since I don't see the story involving the heroes using primals against primals, and Garlemald seems significantly more advanced than Eorzea in weaponry.

We know that Ceruleum is concentrated and refined Aether, and Aether is released when any living thing dies. We also know that during the many assaults by the Imperial Legion the beast tribes are fervently praying to their gods for deliverance.

It seems reasonable that the release of a huge amount of Aether, through the destruction of the Agrius and the death of Midgardsormr, is enough for the primals to take physical form and answer their followers prayers.

I don't think that's actually supported in any official lore, but it seems to follow what we know of the world and it's primals.

Actually, it sort of is covered in lore, not that particular incident but the conditions, if turn 13 is any indication.

[Nalien]

Something tells me the moment this is going to have something to do with Garlemald, since I don't see the story involving the heroes using primals against primals, and Garlemald seems significantly more advanced than Eorzea in weaponry.

Garlemalds stance is actually one of the reasons I'm fairly certain we'll be summoning Primals soon. In 2.4 they mentioned that if Garlemald learned that it wasn't just the beast tribes of Eorzea that could summon Primals, all remaining doubt for a second Eorzean Campaign would likely vanish and they'd begin their march again. That's some heavy foreshadowing in my opinion, combined with the fact that Primal summoning is meant to be a piece of upcoming content, and the logic behind using Primals (and Auracite) to defeat Ascians, and I can see it happening in 2.5.

My prediction is something like;
2.5 Part 1 - We learn how to summon Primals similar to Iceheart, likely from our expedition into the Keeper of the Lake (Iceheart told us to go there), using that and auracite we push back the Ascians. Perhaps they summon Zodiark prematurely in retaliation and that's the Mystery Trial, perhaps not. Either way they are defeated for the foreseeable future. I get the feeling Lahabrea might survive and come back eventually though.
2.5 Part 2 - Garlemald takes note of our use of Primals and resumes its Campaign to conquer Eorzea. This pushes the Eorzean Alliance to desperately seek Ishgardian aid (See: the new years poem), however Nidhogg awakens and they becomes preoccupied, forcing us to join the Dragonsong War in 3.0. The Battle of Ishgard being either the first wave of Dragons, or a sudden offensive for Garlemald (since Ishgard would play a pivotal role and they're currently no where near prepared for a Garlean invasion). Either way, our role in resolving the battle results in them welcoming us in come 3.0.
3.0 Part 2 - The Dragonsong War is resolved, Ishgard formally joins the Eorzean Alliance, Ala Mhigo here we come!

[Zohar_Lahar]

It also needs to be remembered that, frankly, the 1.0 intro video is very nearly an unreliable source these days; it got a bunch of details, large and small, about 1.0 wrong due to shifting development priorities and design alterations. I would not be surprised at all to learn that what was originally planned for 1.0 concerning the Primals and the release of the seal was not at all what actually went into the game in 1.0 and ARR; from trailers, in fact, we know an entire questline, including multiple involved cutscenes, concerning Titan never made it into 1.0, even before the earthquake disaster.

Since they never bring up the pillar of light at any point in A Realm Reborn's main scenario quests on the subject of primals, I think people are relying too much on an ancient FMV that only has a tiny part shown again during the current game.