The Kid's AgeRucks states that the Kid joined the military because "School ain't workin' out." Assuming shared school-ages between Earth and Caeldonia, he would drop out of highschool (age 17), opt out of college (age 18-19), or drop out of college (19-20). That gives us a four-year age-range. After his five-year tour (I think it was five), that puts him at 22-25 years old. His second tour was interupted by the Calamity, which gives us a range of 0-5 additional years, but more likely 1-4 (at least one full year served and at least one full year left). This give us a final range of 23-29, not a child by any means, but still young enough that fifty-or-sixty-something Rucks would be justified calling him "Kid."
The Bastion never has enough power to rewind time far enough.While it's not explicit, when starting a New Game+, Rucks' last words to the Kid at the end of the game are heard, right before the narration starts at the very beginning with the Kid waking up. This could easily suggest that while The Bastion's true function actually works, its intent fails miserably, both in that it will never be able to truly erase the Calamity and that there is no way to inform the past of this fact, causing a recursive loop until someone breaks it.
All replays are canonOne of the endings allows you to rewind time to before the Calamity. With this, every time somebody plays the game can be canon, and all cases of New Game+ are simply a sign that things happened differently before the Calamity.
Rucks is related to the Kid in some wayPossibly even his father. Both have white hair, even though Ruck's could be from age it seems to be implied that white hair is unusual in Caelondia as both the Kid and his mother were ostracized for it. Also how coincidental is it that the man who created the Rippling walls, The Bastion, and helped create the Calamity is alive and so is this one other guy who happens to have the city crest which is somehow connected to the Bastions Reset Button function.
The Kid is the son of AsuraWhite hair, uncanny determination and battle dialogue composed almost entirely of enraged grunts.
The "reverse time" ending goes first, then the "evacuation" ending on the New Game PlusAt first, the Kid thinks it would be a great idea to restore time to before the Calamity. When he finds out this doesn't work, he decides to go along with evacuating everyone, since it's the best option for everyone. Besides, the Kid keeps a lot of stuff on the New Game+, but no one else can remember a thing. He clearly knows a lot more that it looks like.
There are other tribes of people out there in the world who survived.The Kid, Rucks and co. will link up with them after they evacuate the Bastion. Though this is more of the optimist in me speaking than anything from the game.
Zia planned to betray the Bastion to the Ura survivors, while Zulf was completly sincereThink about it; The game pretty much spells out Zulf was a diplomat, so making friends with Caelondians was his job. He most likely planned to get back in touch with the rest (now that he was no longer forced to stay) and broker a peace deal between the survivors. When he found the journal and found out what cause the calamity he was pissed off and tried to restart the war instead. Meanwhile think about Zia's motives; before the calamity every Caelondian she knew either mistrusted her, played with her feelings and stabbed her in the back or otherwise gave her nothing but Fantastic Racism. While it's possible she didn't hold a grudge (since she was culturally Caelondian anyway), keep in mind that her song/theme is basically (well, see my next WMG, but still) a threat aimed at Caelondia from the Ura. Therefore it's possible that when she slipped away to investigate what Zulf told her, she disgarded her harp for being Caelondian, met the other Ura with the intention of betraying The Kid and Rucks to them, realised that they were still jerkasses (given how well their meeting went) and decided to side with The Kid when he turned up to rescue her.
The song Zia sings actually a lot less warlike than it sounds.Reading the lyrics it sounds a lot like a threat from the Ura to Caelondia. However when you think about the double meanings in the other songs with lyrics ( Zulf's theme is about going home while he's slowly dying, however it also echos The Kid returning home to finding his mother had died and someone had simply pocketed the money he sent back, Coming Home has the going back in time business and The Pantheon is both Rucks having a Rage At The Heavens and lamenting his own mistakes) it could just as easily be a warning (after all, if the Ura had religious beliefs against living above ground and they were on good enough terms to send a diplomat they might be inclined to "warn" the Caelondians. It could also imply an intention to build stronger ties; "So build that wall and build it strong/'Cause we'll be there before too long" could mean "Make sure you're well defended, because we're going to attack" or it could mean "make sure you've got some good housing sorted out for when we join you".
The song is the Caelondian perspective on the Ura.This is a theory I saw represented in the main page, but it's not here so I'll add it. The logic goes that the song is indeed talking about how the Ura are going to come and wipe out Caelondia in spite of the Rippling Walls... but if Zia is from Caelondia, where would she learn a song like that? When you first begin to hear it at Prosper Bluff, Rucks says "there the Kid hears something he ain't heard in a long while. How's it go again? Yeah, that's the one." Indicating the Kid's heard the song before, and implying he himself has as well, so where did they ever learn it? The song wasn't written by the Ura, it's form Caelondia. So it's not the Ura saying "OMG we're so badass and we're gonna beat you," it's the Cael saying "OMG the Ura are so scary and we're all doomed." Not to mention, this ties in perfectly with how the Calamity was caused by an attempt to stave off the threat of the Ura, while the Ura were actually trying to make peace; and with how Caelondian-raised Ura like Zia aren't allowed to have contact with their homeland, so neither side knows all that much about the other. To the Cael, the Ura are like some mythic boogeyman, ambassadors be damned.
Rucks is actually the Kid. He seems to be the only one to have partial memory of the events occurring, and tells the full story to Zia, even parts that he probably wouldn't have heard otherwise. Because of the damage to the Bastion, instead of sending back all of the occupants with their memories intact, only the Kid (the one who pulled the switch) makes it back to Caelondia about twenty or thirty years before the Calamity. They dress nearly the same, they have the same hair and (from what I can tell) eye color, and Rucks seems to be vaguely aware of the workings of the time loop caused by restoration.
The Kid is Roland Deschain.Based solely on the Ground Hog Day Loop nature of the game's plot, and the fact that the kid can equip himself with some badass revolvers. There's not enough evidence otherwise; this theory just seems rather cool.
Rucks wasn't lying about his careers.He's at least 20 years older than the other 3 main characters. So who says one can't move up the ranks of an organization? Maybe the reason no one expects someone to take multiple tours of duty as a Mason is because they expect you to either retire or change career paths. He could have started as a Mason, moved up to being a Trigger and obviously ended a Mancer.
Rucks has had a literal Multiple Choice Past.It's heavily implied in the game that this isn't the Kid's first go 'round. Why would it be Rucks'? Just as the game has kid return his next attempt with improved weapons, Rucks' might come back remember another career path in his life that somehow helped lead to the calamity.
Rucks knows Cave JohnsonBecause I have added this moment of epicness to my own personal canon.
Caelondia eventually becomes the city of Oneiros, seen in Clive Barker's UndyingThink about it. Both were once magnificent cities destroyed by a mysterious disaster, and remain as chunks of masonry floating in an infinite void. Both also feature pieces of land spinning up to form walkways for the player's convenience. Sure, Oneiros looks a lot more decrepit, but that's because it's been in such a state for so much longer.
Zia was deliberately manipulated to give Caelondia a reason to use their new weapon.The young man who befriended/seduced Zia was an agent of the government, who was engineering an opportunity to do what many of the people of the city still wanted to do - attack the Ura and eliminate the threat of war once and for all, and/or take revenge for lost loved ones. He might've been motivated by lost family, or they might have offered him some form of payment. Either way, he won Zia's trust with deception, deliberately turned Venn against Zia, gave Zia the idea to run away, and told the guards where she'd be so that the government of Caelondia would have something to point at when people criticized them for attacking the Ura during what was apparently peacetime. ("He was using his own daughter to sell City secrets to the Ura! Surely they were planning an attack!") Since the Ura were making overtures of peace - see Zulf's presence there - they needed something like this so that they could act with impunity, and Zia was just a convenient pawn to them.
The Ura attacked firstIn the Ura-Caelondia war the Ura made the first move and ultimately lost (it says somewhere in-game that they surrendered). Zia's song, Build That Wall, implies an Ura invasion rather than retaliation or an attack during the war. Gon' build that wall until it's done/but now you've got nowhere to run and So build that wall and build it strong 'cos/We'll be there before too long So the Ura took on a target too big for them and lost in the end. Of course, it's hinted at that Caelondia was a colony of an empire somewhere far away, so the Ura had good reason to want to attack them, but it sparked widespread fear and hatred of the Ura that made a weapon that could cause the Calamity something that the people would want. It's possible everything could have been avoided if the Ura had just left the Caels alone.
The Bastion causes the Calamity.Tying into the nature of the stable time loop of the Restoration ending, the reason The Bastion never rewinds to a point before the Calamity is because the use of the Bastion itself is what caused the Calamity. In the rewind endings we see Ruckus next to the Monument, and we know he has a lot of regrets in his life to the point almost having a death wish. He might have been helped along to make the decision to use the powers of the Bastion to turn things back to the point of averting the war with the Ura, or maybe one of the other people involved with the Bastion's construction gave him false information, but in the end the first time the Bastion was used, it caused the Calamity, and thus established a 'save point' to rewind back to the next time it was used. It never can go back to a point before the game occurred, because it had never been used to establish a point of return before that moment, and it just so happened that the process of such a task had unforeseen consequences for the rest of the world. Rucks did say the thing was unfinished after all.
When Zia's father sabotaged the Calamity Cannon he also sabotaged the Bastion to stop the rewind feature from working correctly.Judging by the beginning of New Game Plus mode, the rewind point starts just as the Kid is waking up in his bed, the time when the Calamity happens. We know her father was working for the Mancers who were also designing the Bastion if Rucks is to be believed. He sabotaged the Calamity Cannon out of a desire for revenge for what the Caelondians put him through, and if he knew they were also designing a failsafe to undo its effects, he'd most likely break that too so that his revenge couldn't be recovered from. Disabling it entirely would have risked drawing attention and made them avoid using the Cannon long enough to find his sabotage, so he just set it to only go back to just as the Calamity happened. This would work perfectly - not only would they not be able to do anything about it, but the people who had made him suffer would have to relive him killing them again and again, forever. Talk about a dish best served cold.
Bastion is set in the same world as Thief....the City is another, older colony from the Cael homeland, and Rucks and Garrett are distant relatives.
The Distillery works by The Kid taking a shot of each beverage before taking the skyway of the The Bastion.Which is why he can only use more that one drink after he has gained levels, otherwise he would be too drunk to operate in the ruined world. Also counts as needing some liquid courage to scavenge the broken remains of the his world.
The Caelondians and Ura are gnomes, rather than humans.Their short stature and large heads aren't just part of the art style, that's their real proportions. This explains why there are so many huge animals and plants around; they're really just regular sized and wouldn't be a threat to a human, but to gnomes they're very dangerous.
Rucks created the titular weapon Red wields in Transistor.The transistor shares voice actors with Rucks, true it sounds more youthful however it makes sense Rucks might design it based on an idealised version of his younger self. Also the transistor's ability to create a tactical view that allows accelerated movements could well be a form of time manipulation and Rucks helped create the Bastion, who's purpose is also to manipulate time.
Caelondia is XenThe Aperture sentry turret was right. After the calamity all the human characters died off, along with most of the wildlife, leaving only the creatures you see in Half-Life, who live in a different part of the continent than you see in the game. Whatever sent the turret also sent it back in time to before all this happened.
The game takes place in the Bioshock multiverseThere's a city (Caldonia). There's a man (the Kid). And the Bastion's the lighthouse