How long does a spell stay active? Is it based on the energy of the caster? Is it based on the energy or number of a group? Is it based on a Patron's (spirit's) offered energy or moon phases? I want to make runes or imbue objects with energy and write a guideline for it, but have no idea how long energies last.
spells can stay active for a long time. it is based on a number of things- energy, concentration, certain times, certain ingredients and level of power and expertise. just find the right mix and it will hopefully work.
Usually the more force you put in it the quicker the reaction. Also if it to charm a item it can last through a good while. I have an charmed (enchanted) that is 30 years old and still as strong 30 years ago. It just deals with the spell, the effect, teh phase of the moon, planets, and the force/ will you put forth.