Being a variant of flan covered in a glistening, jewel-like slime. These are known to cluster in areas with machinery and like devices, seeming to derive energy from their operation, which stimulates them to divide and multiply. Because of this flan's odd ecology, they are often found in cities and near residences where people and, more critically, their technologies are found, this proximity creating a real danger of jelly breakouts. Countless are the tales of villages and small towns consumed whole by a mass of quivering slime.
In the Pithead Junction A and Pithead Junction B areas, large groups of Jellies drop from the ceiling when the switch in either area is pressed. Although, returning to Henne Mines will decreases the number of Jellies at Pithead Junction A to only 3 Jellies.
The Jellies make a popular and convenient level grinding target because if they are killed by Break, they respawn, creating an infinite supply of enemies. A simple set-up is to give one party member a Gambit to cast Sleepga on the Jellies, and the other two party members Gambits to cast Break on them. At this point all the player needs is a Gambit to restore the party's MP through use of Syphon or Charge, and an infinite loop is achieved with the player needing to do nothing but watch the party automatically fight the Jellies.
Jellies are capable to use Divide, which it will create a new Jelly. The new Jelly is divided by the process "binary fission", it shares the exact same level, stats, abilities and EXP as well as LP earned with its parent. Although, if the binary fission Jelly has turned into stone, it would not spawn like its parent. This ability can be exploited fairly easy by reducing the parent's HP to half. Soon after its HP is down by half, it will use Divide and created a new Jelly. Note that Jellies can only use Divide once, restoring its HP and cutting its HP down to half again would not make it use Divide. In conclusion, all of the Jellies should just be killed using Break and the numbers of Jellies to be defeat are doubled.
Depending on the party's level, the Jellies may be entirely unable to hurt them, but if they are able the player should set up Gambits to revive KO'd party members and heal injured ones. Priority should go to the party leader for healing, as if they are KO'd and not revived in time the game will prompt the player to manually select a new leader, breaking the loop. The player should also set Gambits to have the party use Smelling Salts on each other, as even if the Jellies cannot hurt the party with their attacks, they can still inflict Confuse. De-equipping the party's weapons provides further protection against Confusion if it takes effect.
8 Jellies are also fought in the International Zodiac Job System trial mode at stage 12.