Curse those greedy delvers! But what with? I know! How about Aurophobia, fear of gold? Or Barophobia, fear of gravity? And I can hit that annoying wizard with Bibliophobia, no more spells for him!
The TRUE origins of Magic, and dont even get me started on Prophecy.
The spellbook of a long dead wizard that has gained the ability to read itself and cast spells from itself. If could be amazingly powerful as an ally, or use its magic to manipulate and rule a kingdom.