I have a character concept (for roleplaying reasons primarily) of a Sorcerer who started to study the Arcane in an intellectual way and gained a few levels as a Wizard. He is Sorcerer 3 / Wizard 3 now.

However, when he multiclassed into a Wizard, he didn't get new proficiencies, and he already had the Spellcasting feature. Hence the question - mechanically speaking, would he have something unavailable for a pure Sorcerer 6 or a pure Wizard 6, any advantage from the class combination itself?

**Answer criteria:**

I want to find at least one thing, that Sorcerer/Wizard can do and neither Sorcerer nor Wizard can. For example, a Fighter/Wizard hybrid can cast spells in armor (neither Fighter nor Wizard can do that) or cast two spells in one turn. But a Sorcerer/Wizard?