Red XIII is the strong and intelligent red dog that joins you after being rescued from the Shinra Building.  His past is shrouded in mystery, and is eventually unraveled as you progress through the game.  Red XIII is a potent character in battle, being equally balanced like Barret.

Limit Breaks
Lv. 1: Sled Fang-Red XIII opens his fangs and jumps directly through the enemy, causing damage.
Lunatic High-Red XIII casts Haste on the entire party

Lv. 2: Blood Fang-Does the exact thing as Sled Fang, except Red XIII steals some of the opponent's life and MP.
Stardust Ray-Red XIII howls and sends stars crashing to the enemies.

Lv. 3: Howling Moon-Red XIII casts Berserk and Haste on himself.
Earth Rave-Red XIII causes major damage by casting 5 spells in a row.

Lv. 4: Cosmo Memory-Red XIII howls, and the enemy is blasted with a huge beam.  To obtain this, go to Nibelheim and into the Shinra Mansion.  Find the safe, and use this combination: Right 36, Left 10, Right 59, and Right 97.  You must do this in a very limited amount of time, so it takes practice.  Defeat the Loss Number and you'll receive the Cosmo Memory along with the Odin Materia.

Limit Break
Red XIII stands on his two hind feet and howls.