Neither the regular Pokemon Modifier or the Pokemon + Level Modifier works right.
When I discard, go into the grass/cave/etc, what pops up is a glitch Pokemon. For the hell of it, I caught it to see what it'd do and it just lists as #000 and is a questionmark. Of course I didn't save, I remember all too well how MissingNo ruined my Blue game about 14 years ago.
I tried the regular modifier a few times. For Charmander, Pidgey, Jigglypuff, Darkrai, Mewtwo - none of them worked and just the question mark happened. :\