Staff of the Martial Mage

Counts as focus. Gain GREAT WEAPON MASTER feat with this staff.
1/week can imbue martial Stance. Lasts 1 minute (cannot be stopped).
Strength = that of strongest ally in 30 feet.
Hit = 1 charge. 5 Charges = Burning hands 3lvl.
Increase defence by +1 AC while in Stance.
CANNOT cast spells in Stance.
If reduced to 0 HP, make 1 last GW Feat attack against random target in reach (including allies).