Both seeds are used to generated egg PIDs. I kept Seed1 constant and got changing PIDs, Seed2 constant and got changing PIDs, and when I kept both constant I got a static PID.
Code:
Seed1 Seed2 PID
0x0 0x0 C0AAEBC6
0x0 0x1 5878F4C3
0x1 0x0 5878F4C3
0x1 0x1 539702A7
The fact that we get the same PID when Seed1 and Seed2 are reversed is promising. It might not be so hard to figure out egg PID generation, even if we don't have a debugger.
Unfortunately, the egg IVs seem to be coming from some other RNG, one that's constantly changing in the background. I'll need some more testing to see if it advances "Emerald fast" or not.
A few notes:
- The game does not load if the time recorded at the last save matches the time when you reload the game. You'd have to re-save at a different time.
- The egg PIDs are loaded into memory location 02234BA4 (White) when generated. I've confirmed this several times, and it spares the trouble of checking the save files under PokeGen.