Jirachi

Jirachi's solid defenses and typing allow it to check Fairy-, Dragon-, and Psychic-types, such as Mega Diancie, Kyurem-B, Latias, Latios, Clefable, and Mega Alakazam, and it notably is one of the best switch-ins to Mega Gardevoir for bulky teams. Its movepool is huge, allowing it to take advantage of its balanced stats to perform a wide variety of roles. Defensive sets have plenty of support options to make use of, such as Wish and Body Slam, while offensive sets pack just enough power to make use of its wide coverage. On top of all this, Jirachi's incredible ability, Serene Grace, allows it to turn games around in conjunction with many of its attacks, including the notorious Iron Head. However, Jirachi's issues stem from its only average offenses, especially when uninvested, as its STAB attacks' mediocre power offer many opportunities for dangerous Pokemon to switch in such as Mega Charizard X, Mega Scizor, and Heatran. It also struggles to deal with common Pokemon like Rocky Helmet Landorus-T, Garchomp, and Ferrothorn if it isn't carrying the right coverage move.