Employs the life force of leaves to grant Shell to adjacent units.
The Ivalice Chronicles' description
Shell Nymph, also known as Clam Spirit in the PlayStation version and Spirit Nymph in The War of the Lions, is a monster ability in Final Fantasy Tactics used by certain monsters of the treant monster family. It grants the Shell status to adjacent units around the user, but does not affect itself.
Monsters can be recruited to the player's party through the orator's Entice, or a different job equipped with the Speechcraft job command and the Beast Tongue support ability, or if the unit has the Tame support ability.
Obtained
Elder treants have the ability available by default.
Treants can use it if next to an allied human unit equipped with the Beastmaster support ability, available from the squire and other default special jobs (e.g. machinist, holy knight).
Mechanics
Shell Dryad's chance of success is based on the following formula:
The Shell status reduces the caster's magickal power by ⅓ in the damage formula, so it not only reduces the power or hit-rate of spells, but also reduces the weapon damage done by a staff or rod because they apply the wearer's magickal power rather than physical power to calculate the damage. Shell does not affect damage from spells that subtract a certain percentage of the target's HP, though it does affect the success rate of these spells. Shell does not affect the power of healing. The status lasts for 32 clock ticks.
Shell can be removed with other abilities, such as the mystic's Harmony or the templar's Dispel.
Etymology
In Greek mythology, nymphs are nature entities in the form of nubile women associated with a particular landform or location. Nymphs tended to frequent areas distant from humans, but could be encountered by lone travelers outside the village, where their music might be heard, and the traveler could spy on their dancing or bathing in a stream or pool either during the noon heat or in the middle of the night. Such encounters could be dangerous, bringing dumbness, besotted infatuation, madness or stroke to the unfortunate spectator.