A custodian is a guardian that happens upon, or is guided to, a place of great divine significance, in return for a pledge to preserve and protect the site, the custodian will be granted divine power. They continue to use heavy armour and a shield, both now emblazoned with emblems of the deity and their one handed weapon replaced by a polearm with which to stand ever vigilant over the sacred site.
Custodians are chosen due to their steadfastness and willingness to put others safety before their own. Their fighting style, coupled with divine augmentation, makes the perfect defender, able to fight equally well against many as they can against one. The sacred site itself a conduit for a deities power, forcing the custodian to stay within a short distance or be cut off from its power.