Super Saiyan 3
Super Saiyan 3 is the most powerful form of Super Saiyan (in the normal progression, that is). One who becomes Super Saiyan 3 gains tremendous power (though the increase between Super Saiyan 2 and Super Saiyan 3 is less than the increase between Super Saiyan and Super Saiyan 2).
This state is the most visually striking of the three main Super Saiyan levels; the eyebrows disappear and are replaced by a protruding brow, and the hair grows very long. The blond hair, green eyes, and golden aura remain the same, but the musculature increases to a greater degree than Super Saiyan 2. The drawback to this state is that it strains the body, and can only be maintained for a limited amount of time.