Full Odds SHINY MEW in Pokémon Emerald after 22,987 RAs! 

Yes. To get around Emerald's broken RNG seed though, I use the Battle Video method. By going to the Battle Frontier and doing a battle at one of the facilities (I used the Battle Factory for convenience), I saved that battle as my battle video. In Gen 3, battle videos aren't recordings; instead the game saves the RNG frame from the start of the battle and plays through each turn normally from there. RNG in battles only advances one frame per turn, so by starting on the same frame, the same outcome happens every time and is identical to a recording. The trick is that once the battle video sets your RNG frame, it doesn't change it back after you stop watching. You can use this to skip long stretches of time/rng frames. Shiny hunt for however long you want, and when you're finished, go to the Battle Frontier and record a battle video. When you want to start hunting again, watch your battle video first. It sets your RNG frame back to where it was before, so you don't have to worry about hitting any identical RNG frames during your hunt.

​@@Orthros But I can just savey game after a RA session and load it later and keep shiny runways runs right?

@@Stanlyy. In Pokemon Emerald, every time you restart the game your RNG Seed will be zero (0). Let's say you hunt for, say, 10 minutes. If you do an encounter once every 30 seconds, then turn the game off and back on, and do another encounter once every 30 seconds, hitting the same frame each time, then the same exact Mews you got the first time would appear again. If none of them were shiny, they won't EVER be shiny. Now, if you're doing RAs for hours at a time, then you're pretty unlikely to hit the same RNG Frame after resetting - but unless you're always seeing NEW frames, the odds of hitting a frame you've already hit will never be zero. In order to GUARANTEE that you're always hitting a new frame and thus a new chance for it to be shiny, you need to use the Battle Video Method to save and advance your RNG forward.

Totally understand, it's a tough one. Thanks ^^

Yep! As long as you can use a method to obtain the Old Sea Map, you can hunt Mew. A dry battery means that clock-based events like berries growing, shoal cave tides etc. won't function, but the Mew event doesn't rely on any of that.

I'm using a GB Operator - it's basically a GBA cart slot for PC. Their software is an emulator yes, but it's running an official game.

lol what