Jirachi

Jirachi's great defensive typing, good base stats, metric ton of team support, and resistance to Stealth Rock all make it a valid choice for a large variety of teams. It can run a variety of sets, from a utility set to a Choice Scarf set. Jirachi is a great check to numerous common threats, including prominent Psychic-types like Alakazam, Latios, and Reuniclus and Dragon-types like Dragonite and Kyurem-B. With its devastating paraflinch strategy using Iron Head and Thunder or Body Slam in tandem with Serene Grace, Jirachi can tear apart even the most threatening Pokemon. However, it's weak to Fire- and Ground-type attacks, which are very common, and has an extreme vulnerability to Spikes from Pokemon like Ferrothorn due to lacking instant recovery. It can also get overwhelmed by many of the Pokemon it's tasked to check, mainly the Psychic-types, which are often paired together, making its job harder.