At various locations on the World Map, a random battle occurs but the music sounds sweet and melodic. The creatures that appear won't attack either; instead, they beg you to give them a specific jewel. If you give them the jewel, your party receives a ton of AP and sometimes a useful item.

What is the secret of these strange monsters? Well, if you encounter all eight of them, you get to interact with the Friendly Yan on Vile Island. When you give this cute little creature what it desires, you get to attack Ozma physically. This is the most difficult hidden monster to overcome in the game, and the characters won't be able to use physical attacks without feeding all of the friendly creatures. Being able to attack Ozma physically enables characters such as Zidane, Steiner, and Amarant to be more useful in the fight.

You may notice that some friendly monsters make reference to other friendly monsters, and even give you the appropriate stone to feed to them. This reinforces the fact that there is a certain order in which to encounter the friendly creatures, and the table at the end of this section indicates the order.

The only catch is that you can only find some of the monsters in dangerous, out-of-the-way places. For example, you can only find the Purple Jabberwock in a forest on the west continent, which requires the Invincible airship or the red chocobo to reach. The Friendly Yan's more aggressive counterparts on Vile Island are, in fact, some of the toughest creatures in the game, and may wipe out your party during the effort.
THE ALMIGHTY YANS
If you get attacked by Yans while searching Vile island for the friendly Yan, summon Odin and cast Death on them every round. Also, try to perform the ReflectX2 trick with Vivi, and have everyone else perform their most powerful skill.

If Quina can successfully eat one of these enemies, s/he can learn the Auto-Life ability. Yans have around 20,000 HP, making them tough to dispose of quickly. However, each set of three is worth 28,000 EXP and 3 AP, which makes leveling up and learning abilities much easier!