Nullify all damage to the group.Final Fantasy XII: Revenant Wings description
Apocalypse Shield is Basch's Quickening, obtained for defeating Zalera. Quickenings are built dealing and taking damage, and Basch can effectively build his by tanking damage. Apocalypse Shield makes his group invincible for a time.
Apocalypse (Ancient Greek: ἀποκάλυψις apokálypsis, from ἀπό and καλύπτω meaning "uncovering"), translated literally from Greek, is a disclosure of knowledge, i.e., a lifting of the veil or revelation. In religious contexts it is usually a disclosure of something hidden. Today, it is commonly used in reference to any prophetic revelation or so-called end time scenario, or to the end of the world in general.