The Thunderbird is an enemy in Crisis Core -Final Fantasy VII-. Thunderbirds are powerful enemies with access to the Thundaga spell, as well as powerful physical attacks. It is ill-advised to be in front of them at any given time if they are charging up a Thundaga, and is best to time attacks in accordance to them. In groups of enemies that they may be in, try to defeat them quickly to reduce the risk of being attacked in the middle of attacking other enemies. Having a way to absorb Lightning-elemental attacks will go a long way in fighting these enemies.