This is still related to D/P/Pt, so, yeah...
Well, I've always use Action Replay to get non-legit shinies. In Emerald, I got bored one day, and decided to beat the Elite Four again. I did; it was my twelfth time. So, I went to Lilycove City, and went into the patch of grass to the right of the city, and guess what I find...a SHINY MIGHTYENA! So, I caught it, and(this is where I start talking about Pearl) I transfer it to Pearl version, and I completely forget about this amazing, legitimate, shiny Mightyena in my PC in Pearl, and I erase my save file. This was back in eighth grade, and I restarted it on the bus.