I have read several tutorials on Spellbooks and have a basic understanding of how one works now, but I am unable to find a tutorial -anywhere- that includes how to make spells in a spellbook level-based.. Aka, you gain Critical Strike at level 1 but then something like Tranquility at level 50? (From the spellbook and those spell names are just examples.) I know Defiance ORPG and a few others did this, but I am not sure how it's possible.