Break HP Limit is useless. At 255 Def and Mag Def all attacks that would cause damage over 9,999 can either be avoided or reduced, and any that can't would cause 99,999 damage, killing you instantly ever if you did break the HP limit.

Ribbon guards against all negative statuses, and you get it by using 99 Dark Matters on your armour, or by winning an armour with Ribbon from a Dark Aeon.