Mi’ihen Highroad
This is another very quick trip. As soon as you enter the Mi’ihen Highroad, you’ll be approached by an Al Bhed woman who will implore you to join Rin near the Travel Agency as he presents the results of his investigation.
In short, if you followed the steps in this guide, Rin’s investigation will reveal that the culprit is Rikku, and Rin will present his evidence of actions she’s taken in the preceding chapters (many of which you’ve witnessed indirectly) that led to the Machina problems.
The suspects, and those you can select, include the Chocobo Eater, Calli, Prophet, or Rin himself. And while it is possible to have Rin select anyone, depending on the actions you take, having Rin select Rikku is the easiest because it involves completing every step successfully (not failing the Chocobo Mission, etc.) and nets you a 
Ragnarok accessory as a reward.
Note that the Rikku outcome means you never receive Gippal’s Sphere, which belongs to a different culprit’s path; that line is one of the few the tracker shows as mutually exclusive, and 100% Story Completion is still fully reachable without it.
Who did Rin name as the culprit for the Mi’ihen Mystery?
If you’d like to learn more about the other potential outcomes, check out the Mi’ihen Highroad Mystery page in the Side Quest section:
Side Quests
Interested in learning about the different outcome options for Rin’s Mi’ihen Highroad Mystery, which concludes in Chapter 5? Check out this section to learn about the different culprits, the different choices you can make, and the resulting outcomes.
A cutscene plays out after Rin has identified the culprit; you’ll get another “Episode Complete” screen, and then it’s back up to the Celsius. There’s one last thing to do, though. Head back down and travel to this area of the map to pick up the 
Victor Primoris.
You may have to maneuver the Chocobo around a bit while tapping the 
button. The first time you activate the mechanic, your Chocobo will jump up and grab a treasure chest on the top level, which contains five 
Phoenix Downs. Leave the area, re-enter, jump in the same spot, and this time your Chocobo will drop down to grab the Victor Primoris.
There are a bunch of other treasure chests that you can obtain along the Mi’ihen Highroad, just like in previous chapters, but these are all optional and none of the items are important. The maps and treasure locations are included below for reference.
Mi’ihen Highroad - Oldroad South End
 1 | Phoenix Down ×5 |
| 2 |  Black Belt |
| 3 | 3,000 Gil |
Mi’ihen Highroad - Oldroad Central
| 1 | Hi-Potion ×3 |
| 2 | Titanium Bangle |
| 3 | Holy Water ×6 |
Mi’ihen Highroad - Newroad
| 1 | Phoenix Down ×5 |
| 2 | Victor Primoris |
| 3 |  M-Bomb ×2 |
| 4 | Soft ×5 |
| 5 | Hi-Potion ×3 |
| 6 | Echo Screen ×5 |
Your next destination is the Moonflow. Skip over two locations for now: you’re missing some of the Spheres you need to open up the “Den of Woe” along Mushroom Rock Road, and Djose Temple / Bikanel Desert include a quest that’s easier if you visit the Calm Lands first. To reiterate, your next destination is Moonflow.
Checking the “Mi’ihen Highroad Complete” box adds the Story Completion Percent for the automatic scenes in Mi’ihen Highroad.