Rubicante's attacks alter between Fira, Firaga, a strong physical attack, and the Scorch move. Scorch is a strong Fire-based attack that targets a single character, and Rubicante tends to focus this on the party's melee units (Knight or Master). Scorch can do upwards of 450 damage, so equipping the Ice Mail or any other armor resistant to Fire helps immensely. NulBlaze and Protera should be cast by the White Mage whenever healing is not needed.