Yeah, but this Zapdos is kinda.... old. I already owned it long before 5th gen was released, and long before people found out how to RNG pokemon from XD
legal.exe? It wasn't known until recently how XD mons were generated. There are only two things that support it. The one I showed you and pokecheck.org (must be in 5th gen and uploaded by file).
If you had been gone the last few days you had missed the new development regarding XD mons. They can't be RNG'd on a retail game though, and it is very unlikely they ever will be (you try timing something to a billionth of a second). Check the RNG research thread, or a couple pages back in Discuss My Pokemon thread.