Whenever you obtain a new Familiar or increase its star, it will be registered in the Gallery. As you get new entries or update existing entries in the library, you’ll earn Gallery EXP. This in turn, will increase your Gallery Level, which will also give you the necessary CP Boost. Since getting new Familiars is luck-based, don’t expect to fill up the gallery unless you’re spending a lot of money.
By having specific combinations of Familiars, you can activate the Familiar Fate effect. This effect also gives you a CP boost. After getting the required familiars, you can level up their effects to further increase the CP Boost. This can be done by increasing the stars of the specified familiars.
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