Vitality builds up when you arent playing, as long as you have some stored, you get twice the normal amount of exp, when you play, you use what you have in bank until you go to 0% then you gain normal exp. For a casual gamer like me, i am always playing on double exp.
Spell scroll, if you inspect it, you can see what class it is for. Each spell you have comes in several quality.
Apprentice 1 ( automaticly get it as you level )
Apprentice 2 ( bought at seller and player made )
Apprentice 3 ( player made )
Apprentice 4 ( pristine version of player made scroll )
Adept 1 ( Loot drops )
Adept 2 ( You get to pick special version of spell at 10, 20, 30, 40, 50 )
Adept 3 ( Player made with rare components )
Master 1 ( Loot drop and racial hatred spells )
Now lets take an invented spell for example Nuclear blast. It would go about as follow.
Apprentice 1 - 10-15 damage
Apprentice 2 - 12-17 damage
Apprentice 3 - 14-19 damage
Apprentice 4 - 16-21 Damage
Adept 1 - 18-23 damage
Adept 2 - 20-25 damage + 5 damage every 4 seconds. ( these are special spell youll understand when you reach level 10.
Adept 3 - 23-27
Master 1 - 27-31
All these numbers are approximation and the spell dosent exist, some spell have big upgrades from different quality others dosent do very much. I suggest you dont go for apprentice 2 its not worth it, check on broker for adept1 or apprentice 4 version of your spell or make them yourself.