Testing the roamer generation, with C-Gear and without it for kicks.
non C-Gear IV frames: 0270->0007
C-Gear IV frames: 0002->0009->0002 (New, different value each time).
Can't see it flashing to 000X for each IV call or the shifting (too fast for 1 FPS), but we know it does that.
Seems like the C-Gear is turned off temporarily when the event is going, and is then re-enabled (thus re-seeded) after the event (rainy) stops. It's funny how it is raining when it is cold enough to snow, guess it was an oversight when the game was made :P
Restating it in a RNG-wise approach:
IVs are generated RIGHT as the rain lets lets up. The rain lets up a few seconds after the roamer flies off the screen. So IV's are definitely easy to reset for, but nature and shiny (when we get there) will be nigh impossible at this location on a cart, unless you are extremely extremely extremely persistent (and lucky). It's still an absolute crapshoot because of the rain.
Since respawning hasn't really been tested (haven't seen any info on it), I'd assume it's also respawned after beating the elite four like last gen. But until then...
memory location of White's Roamer
0223D538
still getting this confirmed, but I was able to get this value to change depending on how fast I dismissed the dialogue. This location had the PID of the roamer I caught earlier on a previous save. There's another location that doesn't always show it (02271118).
0223D518 is NOT the memory location for Black's Roamer. It is in another location. I loaded my white active roaming save and the PID did show up in this location, but doing the event with an unactivated event save on black instead of white had it at a different location.
This kind of hints the possibility of having two roamers, we'd probably get both roamers in gray, hopefully :)
The PID is kept in the save obviously, but it is encrypted. In the memory it's in the same region as the egg PID dump (0223EBFC), but this value isn't kept on saving (PID not saved duh)