Tiamat is a boss from Final Fantasy IX. He is first seen on disc 3 when Vivi and Steiner visit the Wind Shrine. Tiamat is fought off screen and referred to as Wind Guardian. He is presumably defeated by the two.
Tiamat later appears as an enemy in the Memoria. He is the second Guardian of Terra to be fought, and appears in the room with a representation of the Invincible where the player can pick up the Rune Claws, a powerful weapon for Amarant. In the Crystal World, a crystal version of Tiamat exists.
Tiamat is slightly stronger than Maliris. Its Twister attack deals Wind-elemental damage. It will drain MP and lower the party's magic and strength stats, so an extended fight puts the party at a disadvantage. Tiamat's Jet Fire attack will put everyone in Heat status. If a character with the Float status attacks Tiamat physically, he will counter with Snort, which will remove the character from the battlefield. Tiamat is vulnerable to Sleep and Silence.
Equipping items with protection from Aero is useful as well as Body Temp and MP Attack. Protection against the Heat status via Body Temp is ideal, but waiting for the status to lift will work fine.
Quina can cast Night every turn to put Tiamat to sleep and the other party members can attack. It is also possible to throw a Tent at Tiamat which has a 50% chance of inflicting Silence on him, which will make the fight easier.
This crystalline dragon is weaker than its flesh-and-bone cousin. Perhaps the greatest boon to the party is the absence of the Float and Snort spells, which ensures all four members will remain in the battle. This Tiamat is highly vulnerable to myriad status ailments. The player should equip the Dragon Killer ability on the melee attackers and cast Ice magic. Quina can learn Twister by eating the crystal Tiamat.