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Gear: the max number you can get (full time) is +86. With proper conditions you can reach +94 (+3 on Besieged, +5 with obi enchantment).
- Kirin's Pole (+10)
- Raptor Leather Strap +1 (+2)
- Mercenary's Dart (+3 on Besieged only)
- Temple Crown +1 (+8)
- Faith Torque / Promise Badge (+5)
- Celestial Earring (+3)x2 Good luck finding these; next options are Comunion Earring / Star Earring (+2)x2
- Kirin's Osode (+10)
- Devotee's Mitts (+6) In case you swap from Temple Gloves just before the Blast.
- Communion Ring / Aqua ring / Celestial Ring / Psi ring (+5)x2
- Melee Cape (+5)
- Ksi Sash (+5) / Deductive Brocade Obi (+10 1min enchantment, 10min recast)
- Temple Hose +1 (+4)
- Susaku's Sune-ate (+15)
Race: This is the MND per Race on MNK w/o subjob
Elvaan = 65, Hume = 56, Galka = 56, Tarutaru = 53, Mithra = 53
Subjob: /WHM (+11), /BLU (+10 with proper equipped spells), /RDM /PLD /SMN (+9)
Food: Goblin Mushpot (+10)
Other
Merits: (+5)
BRD songs: Logical Etude (+15), Spirited Etude (+9) (+17, +11 respectively with Rose Harp+1 / Mythic Hrp+1 / Gjallahorn)
Mind potion: boosts MND 10%-50%
MAX POSSIBLE MND
On Besieged, with a max geared (enchanted) Elvaan MNK/WHM, on Goblin Mushpot, with full meritted MND, songs from a geared BRD and a lucky Mind Potion:
(94+65+11+10+5+28)*1.5 = (213)*1.5 = 319.5
Possible 3195 damage every 3 minutes.