Memorized Spells (5e Class Feature)
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Starting at 2nd level, when you learn a new spell according to the Spells Known column of the warlock table, you choose one spell that you know. You lose the ability to cast this spell using spell slots gained from your Pact Magic feature, as well as other Spellcasting features. You gain the ability to cast this spell once at its lowest level. You regain all spells cast from this feature at the end of a long rest.