魔法防御力アップ [mahou bougyo up] or 'magic defense up' in Japanese.
Final Fantasy XI
Type: Job Trait
Description: Improves defense against magic spells
Other: same tier doesn't stack, no known cap
Other: can be modified with various equipment
Other: the Blue Magic spells that give trait points for this ability are Magnetite Cloud (4), Ice Break (4), Osmosis (4), Rending Deluge (8) and Scouring Spate (8)
Magic Defense Bonus I
Learn at: WHM10, RUN10, RDM25, BLU50+
Other: gives MDB +10
Other: to get this ability on BLU, set appropriate Blue Magic spells worth 8 trait points
Magic Defense Bonus II
Learn at: WHM30, RUN30, RDM45, BLU99+
Other: gives MDB +12
Other: to get this ability on BLU, set appropriate Blue Magic spells worth 16 trait points
Magic Defense Bonus III
Learn at: WHM50, RUN50, RDM96, BLU99+
Other: gives MDB +14
Other: to get this ability on BLU, set appropriate Blue Magic spells worth 24 trait points
Magic Defense Bonus IV
Learn at: WHM70, RUN70, BLU99+
Other: gives MDB +16
Other: to get this ability on BLU, set appropriate Blue Magic spells worth 32 trait points (requires Job Trait Bonus gift)
Magic Defense Bonus V
Learn at: RUN76, WHM81, BLU99+
Other: gives MDB +18
Other: to get this ability on BLU, set appropriate Blue Magic spells worth 40 trait points (requires Job Trait Bonus gift)
Magic Defense Bonus VI
Learn at: WHM91, RUN91
Other: gives MDB +20
Magic Defense Bonus VII
Learn at: RUN99
Other: gives MDB +22
Category: Ability