Origin Form Giratina Pokémon GO Guide: How to Find
Origin Form Giratina will start appearing in five-star raids starting Oct. 9 and ending Oct. 23. Its shiny form will also be available in raids during this time. Giratina is pretty dang strong so try to enlist some friends to help you out once you manage to find one.
Origin Form Giratina Pokémon GO Guide: Counters
Since Giratina is a Dragon-type legendary, your S-tier counter is obviously going to be Kyurem. Being an Ice and Dragon-type, Kyurem is an absolute dragon slayer. Both Kyurem Black and Kyurem White have great options for super effective damage as well as a lack of Dragon-type vulnerability thanks to their Ice typing. Dialga is also a fantastic choice for the same reason, however, it's Steel-type moves won't be super effective against Giratina like Kyurem's Ice-type moves would be. Zen Form Galarian Darmanitan is also a fantastic choice to get off some solid Ice-type damage.