Does a Battlerager wearing his spiked armor do bludgeoning or piercing damage?

@_manoloruiz_ @Wizards_DnDdoes a Battlerager wearing his spiked armor do bludgeoning or piercing damage when hitting with an unarmed attack? bludgeoning unless armor specifies otherwise #WOTCstaff

— (((Mike Mearls))) (@mikemearls) December 30, 2016