Caustic Lore Theories
From Alexander Nox's death certificate, we know that Caustic's mother's name is Katerina Ticacek Nox. We can imply that she owned the Ticacek orphanage, where Tae Joon Park and Mila Alexander grew up under the care of Mystik. From this we can assume Alexander Nox knew Tae Joon Park and they might have even been friends before Nox "died" and became Caustic and Tae escaped the Syndicate and became Crypto.
Here comes my first big theory: Katerina Ticacek Nox IS Mystik.
"Mystik -- I survived my first match, with only two broken ribs. Being as safe as I can, and keeping my distance. Unfortunately, the others are already asking about the Tower. The one Legend you love confronted me on the dropship. I thought he had evidence, but it turns out he’s just an idiot.
There are two others here who are BIG guys. Like your son. Very intimidating. I’m sure one’s a sociopath, but I may have judged the other too soon. His name is Makoa Gibraltar, and he’s here to help Legends survive. I always chalked the Games up to neanderthals trying to prove something. Turns out some of them have a strong code of ethics. Ironically, the only neanderthal I’ve met trying to prove something… is me. Burn this letter as soon as you receive it. Will write when I can. Family forever. --TJP"
This letter from a loading screen shows that Mystik has a BIG son and Caustic and Gibraltar remind Tae of this son. Also, Tae Joon Park, Alexander Nox, Mystik, Katerina Ticacek Nox and Mila Alexander are all from Gaea: the same planet. So, wouldn't it make sense for Nox to be Mystik's son, therefore Mystik is Katerina Ticacek Nox?
My second theory: Katerina Ticacek Nox helped her son escape the law
So, from Nox's death certificate, a corpse was found that was charred "beyond recognition". It is also stated Katerina claimed this burned body as her son's, but wasn't it charred beyond recognition? And if a mother knew her son was dead, she most likely would deny he is dead and since she wasn't there she wouldn't know that it's Alexander. I'm assuming she knows Caustic is her son but we have no proof they are still in contact.
Final theory: Caustic knows Crypto is Tae Joon Park
In the Broken Ghost quest we know that Caustic was the one feeding information to Revenant and when it seemed Crypto was escaping accusations, he randomly pulls a conversation about the Syndicate. Obviously, Caustic could just be smart and this is coincidental, but I think that Caustic knows Tae is Crypto and also knows Crypto wants to go after the Syndicate for what they did.
However we know that Crypto does not know Caustic's true identity yet because of the letter above (the sociopath he refers to is Caustic).
If you think this is true or false, let me know and why!