First of all this is just thoughts on some spells that could work.
Meteo
Lvl:30 MP:74 Magic-Type:Light Magic Skill: Divine
Description: A 3-Hit Multi low damage Spell, May cause severe damage
Confuse
Lvl:76 MP:80 Magic-Type:Light Magic Skill: Enfeebling
Description: May Cause the enemy to attack himself for 6 rounds.
Note* Might increase number of rounds based on Skill ?
Sap
Lvl:79 MP:50 Magic-Type:Light Magic Skill: Divine or Enfeebling ?
Description: Applies a 2-tick drain mp on enemy, Arcana & Undead Take adds a additional 5-tick
Duration of the spell based on skill ?
Bleed
Lvl:99 MP:370 Magic-Type: Dark Magic Skill: Enfeebling
Description: Sabatour Must be in Effect. Enemy takes 80-200 Ticks of damage during every melee or spell cast of the enemy, if the enemy is casting a spell it has a high chance to be interrupted, if the enemy does a tp attack the damage is reduced by 20%.
Duration: 2:00
Recast: ??
Just my thoughts
Let me know what you think I like input and hope to see other spells you all post.