Inventing Spells
Synopsis
Inventing spells is the less efficient way of learning a spell, but on the other hand is the only way Magi can do it completely by themselves (that is without the need of a Teacher or a Lab Text).
Inventing Spells ArM5
The first thing to do is define the spell, what it does, what arts it uses, and parameters:range, duration, and target. That will define the level of the spell.
After defining a spell, the Maga needs to be able to learn it, that means that the lab total for the Technique/Form of the spell needs to be higher to the level of the spell.
Every season that the Maga uses on inventing the spell it gets a number of Inventing Points equal to their Lab Total + Similar Spell Bonus - Spell Level.
When the Maga has accumulated enough points (equal to the Spell Level) then it learns the spell.
Example: A player wants to invent a Creo Ignem Spell - Level 20 Spell - The player has a Lab Total on Creo Ignem of 30 - Each season it will get 10 Inventing points. - After two seasons it will acumulate 20 points, that's the spell level. So it will learn the spell after two season.
Something to keep in mind, every time a Maga invents a spell it creates a Lab Text of that spell.
Notes
Lab Total: Technique + Form + Intelligence + Magic Theory + Aura Modifier
Similar Spells Bonus (see ArM5 pg 101): 1 per 5 levels of the similar spell
Inventing Points per season: Lab Total + Similar Spell Bonus - Spell Level
See [[ArM5] page 95 for full description