How can you find mask of valor in moo moo gx 3.7

Gives:
+1000 All stats

Requirements:
- Doom Horn (Quest Item)
- Tome of Power (Regional Bosses)
- Orb of Fire (Overlord Shop)
- Orb of Frost (Overlord Shop)
- Orb of Shadow (Overlord Shop)
- Orb of Light
(Overlord Shop)

Secret Procedure:
-Sell the Tome of Power
Note: You must have 1M Gold before selling the tome.

Result:
Mask of Valor
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Ang pogi ni john paulo herrera promise