Feral Creature

Feral Creature is a genus of biological-in-nature monsters from Final Fantasy XIII and Final Fantasy XIII-2. They are "products" of the fal'Cie which were created during the crafting of Cocoon and Gran Pulse hundreds of years before the start of Final Fantasy XIII. In Final Fantasy XIII, fewer classes inhabit Cocoon.

In Final Fantasy XIII, PSICOM uses many of Cocoon's wildlife in their bioweapon research, however, several classes probably proved to be of little use in battle and therefore are not part of PSICOM; these are terraquatics, daemons, woodwraiths, and mu (according to Brain Blast quiz from Final Fantasy XIII-2). Gran Pulse's wildlife is not part of any bioweapon research as most humans have vanished since the War of Transgression and a few are are traveling nomads; at that time oretoises, goblins, sahagin, ochu, cactuars, and tonberries are native to "the lowerworld."

In Final Fantasy XIII-2, new feral creature classes move into Cocoon, possibly due to the effects of paradoxes; these are goblins, sahagin and tonberries (tonberries are not part of Gran Pulse wildlife from that moment as well). Two new classes emerge (potcats and wrathwyrms) and chocobos are now encounterable. Additionally, nearly all feral creatures (excluding wrathwyrms) can be tamed as crystals and used in battle. They can also perform their special ability, aptly called Feral Links.

Final Fantasy XIII

 * Beasts
 * Terraquatics
 * Spooks
 * Daemons
 * Stalkers
 * Armadillions
 * Nudibranchs
 * Wyverns
 * Woodwraiths
 * Oretoises
 * Flan
 * Behemoths
 * Goblins
 * Sahagin
 * Ochu
 * Cactuars
 * Tonberries

Final Fantasy XIII-2

 * Beast
 * Terraquatics
 * Spook
 * Demon
 * Stalker
 * Armadillon
 * Nudibranch
 * Wyvern
 * Woodwraith
 * Oretoise
 * Flan
 * Behemoth
 * Goblin
 * Sahagin
 * Ochu
 * Cactuar
 * Tonberry
 * Potcat
 * Chocobo
 * Wrathwyrm

Trivia

 * There are minor changes to names in Final Fantasy XIII-2: mainly nearly all class names are written in singular rather than plural (except for terraquatics), and daemons are now demon (letter "a" was dropped), as well as three new feral creature classes had been added (potcat, chocobo, and wrathwyrm).
 * In Final Fantasy XIII-2, when monster in recruited into the party it can perform its special ability known as "Feral Link" in the English version whereas Japanese calls them "Synchro Drives."