The actual average can be higher than 40mp5 if you use more than 1 mana pot every 2 minutes. How can you do that?

1st mana pot 30s in
2nd mana pot 2.5 minutes in
3rd mana pot 4.5 minutes in
boss dead in 5 minutes

total mana gained on average: 2880

2880/5/12 =48 mp5

Of course if you dont use your mana pot that early or you dont use a mana pot for the last couple minutes of the boss fight, the mp5 is considerably lower.

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