1. A decamark that acts like an egg, with only thunderpunch. (e.g. 0x1D08)
2. Another Pokémon with two moves.
1. Go into the summary of your normal PokCmon and scroll to moves.
2. Go down to the egg decamark and hit A on the first move, and swap it with the second.
If the decamark had only thunderpunch, you can now use - without having it use struggle.
Unfortunately, - has 0 PP, is normal type, and you can't switch to thunderpunch.