Pokemon Go will be bringing back Cobalion to the game once more time as part of the special Raid event which will go on from now until the 23rd of March.
This will be the second time the Pokemon is returning to the game and this time, the Pokemon will be returning with a special Sacred Sword move. Players will also have a chance to catch a Shiny version of Cobalion so even if you already caught one the last time, you could try once more.
Conalion is a Stell and FIgting Type Pokemon which means Psychic, Flying and Fairy Pokemon won’t have much of an advantage over Cobalion. Your best option will be to bring in the Ground, Fire and other Fighting Pokemon into battle so Pokemons like Groudon would be best but other than that, you can also use Garchomp, Hippowdon, and Mamoswine to fight the Pokemon.