Goku as an Golden Super Saiyan
Golden Super Saiyan is a Super Saiyan in which can only be achieved by completing the cycle of normal Super Saiyans, this includes Super Saiyan Five to One. The power increase is 10,000,000,000. Even though only one person can achieve this form, and it has a major cooldown. Which can be noted as it's main weakness. Sadly, It can only be used once a year and lasts for an hour.
This is the original Golden Super Saiyan. See Frenzytech for the God version.
Appearance
The appearance of it makes the hair glow golden a lot more, the eyes, and even the body does it.