Mulligans
General Mulligans
The book and the spellstone represent insane value and are good keeps to make the book better. Firefly is your good one drop. Pyros is good versus control. The keysmith is good versus control to get a counterspell versus them, surprise vaporize on a giant is also good.
The deck plays all the value minions possible, book of secrets is about 75% of the time going to draw 3, and at least 2. Pretty much the idea to just generate value cards every turn, and then reduce the random cards cost with the Leyline manipulator. Voodoo doll with ping is your hard removal. The spells played are for their flexibility and power. The book is obvious include, fireball is a good finisher, glyph can grab whatever you need, the spellstone is usually a cabalist’s tome for 2 mana.
Update: Archangel arugal is now added as he is insane when you play the book of specters, as you will basically draw 6 minions now.