As with most enemies in Zozo, they are dangerous enemies to face. Harvesters use their first and third turns attacking or using the slightly stronger Sickle. On their second turn, Harvesters will use a Hi-Potion to heal themselves or allies. On their fourth turn, they throw Daggers and Mythril Knives at the party, which can be deadly.
Locke can steal valuable Dragoon Boots from them, but they will retaliate by stealing gil from the party. Luckily, the party wins this gil back if they win the battle. The party should use their best attacks to dispatch the Harvester before they get their fourth turn. Bushido attacks, Tools, and Blitzes work well.