A warhammer with liquefying powers.
Forged from the stuff of legends by a great Sacre-Sorcerer. Grants the wielder a variety of different powers throughout the day and night.
Pcs learn of high power magics that allow them to banish weapons and suits of armor to some 'elsewhere' place until such time as they need it. reduces encumberances, gets fewer questions, and when the PCs get jumped by thieves in the ally, they can summon their suits of full plate armor with weapons drawn.
Lesser powers would allow them to summon their weapons from another physical place, drawing them to their hands like Luke skywalker summoning his lightsaber on Hoth.