Spirit

Spirit, or referred to as SPI is a stat that governs how well your Skill/Spells preform. Such as, if you cast Fire with 0 SPI, it will do 80% damage. If you cast Fire with 999 SPI, it will do 120% damage. It also depends on the spell too. Some spells if you have 0 SPI, it will do 0/1% damage, if you cast it with 999 SPI, a good 200% damage will do.

Spell damage is NOT status, it is also determined by random variables to keep your damage from being constant. It may vary by 1 damage point, or by 5000 damage points, it all depends on that one variable. You might just have bad luck if you keep doing horrible damage.