Chapter 65 is live on Crunchyroll!

Manga Spoilers: My money is still on nanites.

Everyone who is susceptible to mind-wipes has them. These nanites also carry the "power" to turn people into titans, but it has to be activated. Rod needs an injection to give the order, and the Beast Titan is able to do it remotely somehow. This would explain how he was able to turn Connie's village into titans at the drop of a hat. It has to have been something that was already there.

My slightly different theory, nanites are still the key, but they are also present in the atmosphere and can be deployed via air. THIS would explain where the titan body comes from and why it's so light. It's just a bunch of nanites strung together, or nanites hastily putting a titan body together from existing air molecules/more nanites. It would also fit well with why Bertolt's titan disappears so quickly - the nanites are barely holding it together.

And Rod's line about having "picked the best titan"? Titan blueprints within the nanites, perhaps? I always thought the titan you got was random, but no, apparently you can PICK your titan! And what about that wild titan that thought Ilse was Ymir? Wasn't he about the size of Ymir's titan? Maybe different human factions had different titan technology?

Another thing - having to eat a shifter to become a shifter... Giving the nanites the order to turn someone into a titan is not the same as giving them the power to turn back. Shifters have nanites with that order, and they get assimilated when eaten. This is also probably why only the Reiss can use the coordinate correctly, because only they have a special brand of nanite in their bloodstreams, one that might be genetically encoded to their specific bloodline. So, you can't just eat a Reiss and become the coordinate yourself.... Well, you can, you just wont have the same level of power.

The only thing I can't fully wrap my head around is the Beast titan... Seriously gives me the impression titans are a RACE, especially now we know who built the walls. Perhaps they were originally "machines" who went rogue?

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