I'm wanting to breed a cofagrigus. I do usually go for any good egg moves. The only one it gets in these games is memento. The only way I can think of to use that move is to attack it with something that has contrary, but would the mummy ability get rid of contrary before the boost?
Cofagrigus with Memento is useful if you want to set up Trick Room in singles and then use Memento on the next turn to drop the opponent's stats and get a free switch in with another Pokémon to get a strong hit off or set up. If you want to use it one your own Pokémon in doubles for example, as long as you don't attack your own Cofagrigus with your other Pokémon first, it should still have the Contrary Ability when you attack it with Memento and get the Attack and Special Attack boosts. A potential pair could be Cofagrigus and Malamar.