@JeremyECrawford Can mc Druid 19 + Wizard 1 scribe 9th level wizard spells into their book and prepare them since they have 9th level slots?
— Aleks (@Twooshorten) March 21, 2016
The PH errata says you must be able to prepare a spell to add it to your spellbook: https://t.co/Uq1bZxWdB4 #DnD https://t.co/qQNxeTHxET
— Jeremy Crawford (@JeremyECrawford) April 22, 2016