Theories

(Actually, theories and a pun.)
Note: The people to which these theories are attributed to are Scratchusernames, not Wikia usernames, and are therefore linked to an outside source.
 * Kidnapper theory: I think that they're either really powerful and well-known figures, or very persuasive with a low profile. A combination is possible, of course. How secretive the whole thing is would be a good hint at how powerful they were; if they were already powerful, they could be using the Elementalists as a public foothold to more power, but they could also be trying to shush it up as much as they can to stay low and do whatever they were planning on doing to the Elementalists as quietly as possible.(@RompingSphinx)
 * Kidnapper theory: Halcyon was kidnapped first and the kidnapper liked Halcyon's hoodies so much that he stole one and wore it during the rest of the kidnappings. (Typed by @ScarlettePhoenix, originally by unknown)
 * Power theory: What if when someone in this world dies [whose] power hasn't been properly contained releases all of it and causes huge natural disasters? So all sorts of funeral rituals would come from a need to contain the power and maybe if a person is nearby someone who recently died when they release their power, if the power wasn't properly contained, then the person absorbs it and that power is incorporated into the person's element? (@ScarlettePhoenix)
 * Talisman Theory: What if the air talisman was made by having that stone or whatever absorb the power of an air Elementalist, and that's how you make talismans? (@ScarlettePhoenix) What if Luna absorbed the power of one of Halcyon's relatives? >:) So if Jay got an Air talisman, what powers of Air might be in it? Would he permanently gain the powers from it if he used it? Could only powerless Elementalists gain powers from a talisman? My original train of thought while I was posting the comment was if it was a Fire tradition to preserve their own fire in something, and they would be cremated in their own fire after they died. (@RompingSphinx) Maybe there's some sort of ritual where all fire elementalists have their power absorbed into a shard of obsidian and then it's given to the family after that person is cremated and it forever after has an aura that reminds people of who that person was when they were alive. No, I did not make that up out of nowhere, it's from a book series I read, it's based on silkshells. What if all Elementalists do that (make 'talismans' that remind their family members of them). For fire, it's obsidian, for water, it would be coral (or limestone if coral is unavailable), for nature, it's coal (compressed bits of dead plants, for light, it's moonstone, and for air it's pumice because pumice has so much air in it. (@ScarlettePhoenix) [Lol that was long ~@percyjacksonhero]
 * Backstory Theory: As a child, [Halcyon's] elemental power was late-blooming, and his dad (I'm guessing that that's who he was talking about in his nightmare) wasn't happy about it. He put him through hardcore, painful training. Eventually, Halcyon's emotions made his elemental powers appear. Fueled by anger and the lessons drilled into his brain, they were especially powerful and his power will likely continue to grow throughout the series. (@AshxNeko)
 * World Theory: The helicopter in Ep.2 is recording them and broadcasting it on live TV. When the main 5+1's family members find out, they revolt against whoever's broadcasting it, resulting in a mini-war which, over time, evolves into WW3 because that's how politics work. When the main 5+1 get out of wherever they are, they return to find the entire world demolished, and they have to survive together again, only this time without anyone sustaining them. Making mountains out of molehills, anyone? (@pinkiepie710) 
 * Pun time! It's so cold because all the fans are on (Originally by @percyjacksonhero; edited by @The_Arts)

Luna

 * Everyone's names have to do with their powers right? (Aurora-dawn, Amber-tree sap, Halcyon-technically means happy but can also refer to a type of seabird if I remember correctly, Jay-bird) except for Luna, which means moon. I got to thinking about how in Avatar firebenders draw their power from the sun, which makes their fire red, so if Luna, say, drew her power from the moon what color should it be? Silvery blue (@blossombreeze)

Jay

 * Jay was supposed to be typing up an essay when he fell asleep at his computer and there were hundreds of Vs on the screen when he was kidnapped (@KeVeg)

Aurora

 * One time when she was little, Aurora picked up a flashlight, turned it on, sucked all of the light out of it, and proceeded to call it a flashdark. (@RompingSphinx)
 * The ham Aurora found in her backpack had previously been her pet pig named Porkey. (Originally by @rgmcbride, edited by @RompingSphinx)

Carter (Running Dude)

 * Carter actually hates to run (@FinchFlame) And he's rubbish at it (@TheEvilChickenNugget)