It has great physical power, as it counters any attack against it with two physical blows followed by its special attack, Throat Jab, which does heavy damage and can likely KO a weaker character. Every other turn, it will perform three Throat Jabs in a row.
The easiest way to defeat Gigantos is to summonPhantom, granting the party Invisible status and causing all of the Gigantos's attacks to miss. Bio spells cause heavy damage to it. Alternatively, the player can also cast Catoblepas or Lv. 5 Death for a quick Death. It is also affected by Stop.