I've recently been hunting for Shiny Pokemon in Pokemon Sapphire and today I found a Shiny Rayquaza after only 2 hours of soft resetting.
It has the same nature as my Shiny Blaziken, the only other shiny I've obtained in this game, which I don't think much of. It's Sassy nature, a pretty bad nature to be honest. I encountered my Shiny Torchic about 2 hours after turning on my game as well, so maybe I just hit the same RNG Frame.
However, something else happened literally 30 minutes after encountering Shiny Rayquaza. I decided I had some time left, so I went to go soft-reset on Beldum. Maybe 10 minutes into turning on my game, Shiny Beldum. Guess what? Sassy nature as well.
Is there anything going on with my RNG Frames? 3 shiny Pokemon with the same nature, one of which found earlier than the others and couldn't possibly be the same. My battery is run dry, so maybe that helps. It all seems too convenient to be a coincidence.
I decided to drop the Shiny Sassy Beldum and start over because people might suspect I'm cheating and I assure you that I'm not. I don't even think I'll mention to other people that I found it simply because I don't want to seem like a cheater.
(I have a pretty odd history with the Sassy nature, actually. Back when I WAS a cheater and cheated the **** out of Pokemon Emerald, Emerald's shiny code forced Sassy nature every time. But I'm not cheating. I even have a
video of me capturing Shiny Rayquaza; no cheating device)