Rock Throw and Rock Slide are the moves you'll want your Mega Aerodactyl to know for this raid.
It also provides Ho-Oh with a better safety net against potential catch attempts.
This makes Ho-Oh very costly and unlikely to have a shot at Great League, but nonetheless it has its niches.
Sacred Fire grants Ho-Oh a 50% chance to win the Melmetal matchup due to the Attack debuff, but that can hardly be considered reliable.
Its strong stats and resistances allow it to be used in many raids, but it is often outclassed by many other Fire-type options.
Ho-Oh was also one of the very first Legendary Pokémon to appear in the show, showing up in the very first episode after Ash faced off against a flock of Spearow to protect Pikachu.