Attack: Dark messenger
Element: Gravity-based attack
Useful skills: Darkside command, mug ability, enc-half and enc-none party
Overview: If Diablos appears to attack weakly, that's only because you're fighting weak enemies; his power is directly proportional to that of his foes. Darkside lets you sacrifice a tenth of a character's max hit points to deal a triply powerful blow; a worthy sacrifice to finish off a weakened opponent. Mug is vital for finding rare items necessary for weapons upgrades and Quistis' blue magic. Enc-half and enc-none eliminate the headaches of random encounters.
source:here
