Xenoblade Chronicles 2: Part 31: Find That Little Roc Thief!
11When Rex and his team were on their way to their ship to Mor Ardain, a Core Crystal, Roc's Core Crystal, started glowing. He was regenerated ready to be resonated with a new Driver. A new Roc without his past memories of Vandham...
As they continued on their way, Rex suddenly had Roc's Core Crystal's swiped away by a Gormotti kid! It was time to chase him down!
The team tried to catch up to the kid, but he quickly got away with a ship. So Rex's team had to take a different one. It looks like it was going to Gormott, itself.
The ships docked at Torigoth, so the team had to ask around for the kid's whereabouts.
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Besides me doing a bit more questing, you can ask several people for the thief's whereabouts, but specifically focus on Nugby at 11:32. He tells you that he left the town, and that you should talk to Otto about him at Nocclia Timber Site.
At 20:35, I find Otto. Unfortunately he can't really help with the search, but you can get some advice: You can either Otto for some hints, or hopefully have some Blades with the Field Skills of Keen Eye and Fortitude to help you follow some footprints. The footprints will be glowing red.
As it would turn out, the footprints, whether or not you tried to follow them, led to Umon's Shipyard.
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The Gormotti thief was found with several other Gormotti kids. They tried to unleash some bird monsters on Rex's team, but the team dealt with them swiftly, and Rex was able to get back Roc's Core Crystal from them.
The Gormotti kid thieves had to confess to them why their leader, Rhys, tried to steal Roc. They wanted to bond with a Blade that could help them avenge the destruction of their village, including the loss of their families. This was a very risky measure at their young ages, because failure to bond with a Core Crystal could instead leave them to die.
Rather, Rex wanted to help the kids take revenge on the bandits that ruined their lives. Just on time, another kid appeared to report to Rhys that the bandits were about to attack Torigoth, thanks to Rex's team taking out Consul Dughall.
The team will go to Twin Trunks Hill to find the bandits, while the kids are to tell the city guard about their presence there.
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On the way to Twin Trunks Hill, the team encountered another foul Ether Miasma. Rex figured it was now time to resonate with Roc to deal with this.
As it was foretold, Roc recalled no memories of his former time with Vandham, but he was more than happy to now serve with Rex as his new Driver and try to continue on Vandham's legacy.
Likewise, in reference to this unlocking more of Roc's Affinity Chart requires you to keep increasing your Merc Level. So keep going through those Merc Missions!
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After a bit more of a walk, the team finds the bandits hideout at Twin Trunks Hill. They were Drivers with Blades, but Rex didn't want the team to kill them.
The bandits consisted of Benjamin the Brain, Cartbreaker Grzeg, and Menancing Jo.
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After beating the bandits, a bunch of Ardainian soldiers arrived. Rex and his friends ran away from the scene to let the soldiers pick up the bandits. Rather than taking their lives, they allowed the bandits to live to make them pay for their crimes.
Back at Argentum, Rex explained to his crewmates there about the reason for the Gormotti kids' behavior. He had the idea that they should be raised as salvagers. It will be hard work for them, but at least now they had a new place they could call home.