Hyper transformation

The Hyper transformation is an extremely powerful transformation initially used by Sonic with the Super Emeralds, and he later achieved the transformation naturally while training in the Other World, and later taught it to Sono. It is unknown who invented this transformation, but it is likely the Common Ancestor was able to use this transformation, in addition to other Hedgehogs, a few Saiyans, and even a couple Humans.

Advantages
The Hyper transformation is commonly used by Sonic due to being able to provide the power of Super Saiyan 5 with minimal ki consumption, and can be used by people outside the Saiyan or Hedgehog race, including Dr. Eggman in Silver's timeline. Another advantage over Super Saiyan 5 is its appearance, while sharing the same hair color, is generally thought to be more visually appealing than the former transformation, with similar hair to Super Saiyan 2.

Disadvantages
While the Hyper transformation has many advantages, and is Sonic's preferred transformation during the Tournament Saga and later arcs, it is not without its drawbacks. The biggest one is probably the fact that it can take up to 50 years for most people to master the transformation, though Sonic could use it with the Super Emeralds at the age of 13, and Sono could use it without any assistance at 15. Another drawback is that the Hyper transformation, combined with Kaioken or the Super Emeralds, changes color from white to flashing colors. There are a few more drawbacks, but those haven't been explained yet.