This is a long post covering a lot of ideas, so take your time. This is a post trying to gain insight into what the future holds with what The Travellers are trying to accomplish. This concerns not only the ending of this season (Season Five) but in truth next season (Season Six) and possibly the conclusion of the series. This post is a large consolidation of many of these ideas, so yes it is BIG. Those that aren't interested heavily in TVD lore and story-lines, leave now. Also if you hate reading a lot, I'd leave. This is NOT a thread meant for "easy-reading". This is meant for fans and TVD Wikia users.
Make sure to add any further insights, changes, or expansions below. I love to read them all and expand and include your ideas as well. Feedback is always welcomed by me.
Also, if any areas are hard to understand or unclear, mark them out below and later I will edit my post and reorganize that area to make it more "reader friendly" (I'll post below you to let you know that it has been changed and include a snippet of the edited portion only--unless it's just minor corrections or similar edits), though this may lengthen it.
I'll call it "Marcosa" in relation to an old reference to a bad place called "Carcosa" (of course for those that watched True Detective you may know of what I'm talking about; or if you know enough about Lovecraftian Universe stuff)...
Anyway, nothing good is coming from this spell, but I think for now what The Travellers will try to do is to "balance" out their leader Marcos with another spirit--a good one; as in the show it seemed he got one that came from the Other-Side that was evil...from its appearance alone--to balance it they will need Stefan and Elena.
This is a partial bit of a post I made about Katherine's death, and it is relevant to what has transpired:
"I speculated above that Katherine was "spirited away" by the dark spirits (or at the least something similar to them), but I wonder if something else could explain what happened as well--but I doubt this, as I expect the new doppelganger of Stefan's if killed to get sucked into that very same "dark void" as Katherine. As I said, it may very well be the beginning stages of The Travellers getting prepared to cast a massive expression ritual spell via expired/killed doppelgangers. Which means eventually they will try to kill Stefan and Elena to get their ritual "in place". I further imagine that they will successfully kill one of the main cast members in the process, leading to something huge in the future."
"...for example we don't know if Luke and Liv are part of a small Traveller group that are after the doppelgangers or the whole "scooby-gang" OR if it's also Sloan's group as well--we don't know if they are a united front..."
Now on to the new stuff:
I guessed in the past that the Travellers were going to perform a massive spell of some sort. They have done this, but they seem unfinished however. We need to find out how Elena and Stefan fit into this little puzzle. It seems like Stefan and Elena are the "ultra-goodies" in the show (angelic like); Amara and Tom were similar; Silas and Katherine were similar; BUT, we still have Tatia with no one to match (or they will very soon trying to use Stefan, but since they used the spell I doubt anymore are out there)... Which means either another Stefan doppelganger is out their OR Nature threw The Travellers a curve ball to "balance" the equation (a doppelganger that can't be found, but that is equally attracted and involved with them). If this is true then Damon will be the key to saving EVERYONE: Stefan, Elena, her brother, Bonnie, et cetera...from what would more than likely be a certain death. I've said this before and I'll say it again, I truly think that Damon is Nature's way of completing it's balancing act with the doppelgangers and he is a hidden variable in this whole scheme--plus he is from the correct bloodline to make it true.
From the looks of things it seems like Marcos used The Anchor as a bonding point (as his fellow Travellers died and passed through Bonnie, linking her to a spell in progress--not only to the doppelgangers ON the Other-Side but also to magic's minions: The Spirits, possibly Nature) and this allowed them to connect the spell even to her and The Anchor. So I may have been wrong in assuming that the spirits (those that seem to govern "normal" magic that is based off of the rules of nature; the kind the Travellers detest--something I was partially right on and some things might be worth re-reading to rethink over here: Travellers & The Otherside) were actually a completely separate faction.
The Travellers may have, with the casting of the original immortality spell AND the anchor created a means to control their "beautiful step-sister" and to also control where some go when they die (the supernatural, though I imagine to them vampires and werewolves were just the icing on the cake, they truly wanted the witches--possibly, but perhaps Marcos will make things more clear for us, if he doesn't just start killing everything in sight), even creating possible new realms of "death", possibly where Katherine is now, a.k.a. purgatory...
Now with the casting of this spell on Marcos and seemingly he being "linked" or even merged power wise (I would assume; making him another new type of immortal...and for all we know the anchor moved with him as well) to something "dark"--which I imagine is literally the same exact entity and being that dragged Katherine into purgatory--also known as dark spirits, the thing that normal witches have feared their ENTIRE lives while practicing magic, I imagine this means that war is truly come to Mystic Falls, witches, and most of the supernaturals. We may even see The Originals show up on this eventually with so much at stake.
We still don't know what they want with the living doppelgangers, but it is obvious that it will either make Marcos FAR more powerful than he is in this new state, or changing the nature or balance of magic around the world; Stefan & Elena may also have the ability or possibility of contesting his ability of power and to bring the world back into peace, somehow. But, this more than likely means that either Stefan or Elena will die (or both; considering that Marcos drank their blood to gain power, it may be similar to when Alaric was using Elena as his life-link--to beat him they may need to sacrifice themselves to save themselves and possibly far more than just themselves) no matter what at the end of this season's finale.
I'm glad TVD is starting to put things back together, it's beginning to feel more like its old self than a wandering pile of ideas that aren't quite coming together.
Anyway, it is important to remember that we have Liv, Luke and Jeremy setting up an alternate plan behind everyone's backs (and I wonder if this may get Elena, possibly Stefan as well--or vice versa--killed to prevent Marcos from gaining power ultimately; though truly to give Elena power to fight back). In a very quick snippet from earlier in the season it looked like Damon attacked Matt, to the point of killing him (though he does have the ring, so I'm not sure how "earth-shattering" that death would be), it makes me wonder though--if true--why he would do it...
Lastly, I'm assuming that Marcos forcibly took something from The Other-Side via The Anchor using this massive expression sacrifice spell (with doppelgangers being in different planes, Silas on the Other-Side, Amara with the humans, Katherine on the Other-Side though presumably in their version of limbo/hell/purgatory, and once again we have Tom as a doppelganger going somewhere--BUT not appearing in front of BONNIE (this must mean something big). Then Marcos uses the living doppelganger blood to connect himself to all of them, and the death of his comrades to link himself to the anchor and the "sacrifices" to link him to whatever he "pulled" from beyond (the shadow). Now I assume with Elena and Stefan he needs to get a normal spirit, rather than just a dark one to complete the spell completely and to BREAK the inability for all Travellers to use normal magic--meanwhile he will be something very powerful, and if he gets the last "good" spirit then I doubt he will ever be stopped (essentially he will be a demi-god; or at the least something in control of both sides of magic and possibly the balancing force that presides over magic itself...if that doesn't make him a demi-god I don't know what would). But, this may just be an extreme play/spell to "lift" a curse (as we haven't heard yet the full details on why exactly The Travellers ARE the "ugly-step sister") that The Travellers have on them to perform magic done by normal witches.
If that is true, then in the next season the Travellers may start to make their move to become rulers over this world (I imagine The Originals would notice this stuff at some point and NEED to come as it should even affect their baby, since she is one-third witch...if the Travellers do anything to the witches that is. From Liv's story, it seems they hold a tremendous grudge against witches (only a few don't, that being a rebel group withing The Travellers; like Live and Luke, who possibly knew and were conspirators to some degree with Silas). Otherwise, the next season will be simple as well. While the Travellers will pose a threat, the main baddie will be Marcos, with right now unnamed and untold powers--but I imagine close to a wraith in some aspects, like body jumping, mental control, magic, possible limited immortality, etc (though their are a few creatures in the books he could be like as well, we will see)... The fact that Elena is having weird dreams in the next episode could even portend that he is somewhat similar to an Incubus, if he is causing this.
At the end of this season I'm sure something truly calamitous will befall our main cast, that they will need to recover from next season.
This may mean that a main character will die--perhaps EVEN two. But, even if a main cast member(s) does die, Bonnie may end up breaking the anchor--using Liv possibly--and then we will get quite a few people back many who will die fairly fast in a deadly battle with The Travellers. But, I have no doubt that if someone truly dies for good this season--especially if BOTH Stefan and Elena are in trouble--Bonnie will remove The Anchor and destroy the veil in attempt to utterly obliterate the ideas and ability for the Travellers to further control the situation. This would be the turning point. Most likely the point when a cast member will permanently die (I imagine it to be Bonnie, Damon, or Stefan), and Stefan & Elena will lead a charge back against their new enemy, possibly changed with the veil down and new allies behind their backs. Though if Bonnie did this, I think the spirits would return her to life for her selflessness in protecting the world and literally, them.
On another off-topic, concerning the possibility of the veil dropping, again... Some may just run off to New Orleans (screwing up Klaus's AND Elijah's plans, as they never planned on it happening; like Kol returning...or even more of their siblings, perhaps even their father or mother...though doubtful since her remains were consecrated, but we don't know if that means that she can't come back if the veil were truly dispersed). BTW, IF Kol came back, I imagine it may be possible that another sibling will come back or their father--just to run him away from Mystic Falls rather than staying there to torment them and to get revenge--he literally won't have the time to think about such luxury. It's also possible that Kol will come back, try to get his revenge only to find either Elena or Stefan changed into a new type of being (or even Marcos himself may stop him, who knows) and literally show him--very fast--that his only weakness as an Original is NOT the White Oak Stake (using a new ability). Thus scaring him off from Mystic Falls and into his new life of New Orleans...