Help on spell fire resistance

Current upkeeper: Pickett
Casting time    : 8
Spell cost      : 250
Spell type      : resistance (single)
Spell words     : Mahl ex fire
Affecting stats : Wis, Lvl
Affecting skills: Arcane power, Mastery of shielding, School of fire
Affecting spells: fire resistance
Adds some resistance against given damage type. Different types can be
stacked but effect can be somewhat less if there is already resistance
spell upon target.

Fire bolt < List > Firefly sting