The Adamantoise is an enemy from Final Fantasy IX. It can use Limit Glove to destroy its opponent in one blow. It is recommended to strike its weakness to Lightning-elemental attacks by using Vivi's Thundara spell, as well as keeping the party's HP up at all times to avoid its Earth Shake attack, which Quina can learn by eating the enemy.
This spell can also be avoided by equipping equipment that absorbs Earth-elemental attacks, or by simply having Float or Auto-Float on at all times. It can be defeated in one blow of Steiner's Iai Strike if it connects, or through the use of Mustard Bomb or Freeze. Overall, while being a powerful enemy, it is not difficult to defeat.
Adamantoise is a portmanteau of "adamantite" and "tortoise".
Adamantite and similar words including Adamant and Adamantine are used to refer to any especially hard substance, whether composed of diamond, some other gemstone, or some type of metal.