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In a campaign that i'm playing in, my my Wizard 3/Cleric 2 has come across some new spells, the one in question being a 3rd level spell. Because of multi classing rules, he has 3rd level slots, but no spells of that level. Would it be possible to transcribe this spell into his spell book because he has spell slots, even though he does not currently have any of that level? If it matters, the subclasses are Bladesinger and Light Domain, and the spell is Animate Dead.