>>54932304>Pretty much every legendary is duoable barring Lugia.Unless the legendary is really frail or has a quad weakness, you need a ton of lvl. 40+ legendaries, a ton of lvl. 40+ shadow Pokémon, and//or weather-boost to consistently duo. You'd either have to bot, burn tons of raid passes or have way too much free time to hit such a threshold with two accounts.
