Rex gained his 2nd mystic treasure with a living consciousness.
According to the red blob living consciousness that Berserker already started referring to as Baby Vamp, the Vampiric Armor was the personal armor that was previously used by the esteemed Sword Saint before his death.
In the great battle that led to his death, the armor suffered a lot of damage, leading to it dividing into 2 parts which became scattered in different locations with time.
Lord Asuka was only able to bury one before he buried his master.
As for the other main part of the armor, Lord Asuka gave up on it and left it as an inheritance for the potential candidate for the main inheritance.
Through his incredible powers as a Super mystic warrior, he was able to configure the armor in a way where its future wielder would automatically be connected to the main inheritance.
