Ima just start from the beginning there are 3 types of 4-star characters stepups ex'es and bounty fests. Step-up Stepup characters are in every banner and come out whenever basically you can tell if a character is a stepup if you can buy it in the exchange shop. Bounty Fests: or legendary characters appear in bounty festival scouts that come once a month and can either be a new character or a repeat of multiple bounty fests. Any bounty fest can be gotten on bounty festival banners. Most featured characters for step-up scouts are bounty fests. Ex: Ex'es are the most powerful class and come out 5-7 times a year. This applies to new ex'es as currently there is always an ex rerun(where the ex comes back for cheaper) on rotation. I will add more to this if you need me too.