The Deep Power Stones are objects that appear in the Sonic the Hedgehog television series. They are two stones with powerful capabilities that are capable of either producing incredible power or causing utter destruction.
The Deep Power Stones are two black stones with visible cracks on one side. They are also surrounded by what appears to be a yellow energy bubble. Overall, they look like two halves of the same stone. The Deep Power Stones can either be a source of limitless energy or cause utter destruction, depending on how they are joined together. If joined together on their jagged sides, they become a source of destruction, but when they are joined the other way around, they produce great power. This power is similar to that contained in Power Rings, but increased ten thousand times.
This energy can be harnessed by any living being, unlike the Power Rings which only work on Sonic. People harnessing their limitless energies are surrounded by a white force-field with glowing particles floating around them. These wielders also gain an increase in strength and speed far greater than what Sonic obtains when using a Power Ring. After the stones are used, they seemingly disappear, with no explanation having been given for their disappearance. In addition, some remnants of power will remain after they have been used to empower a person, as such users will be surrounded by a purple aura, which grant the wielders increased strength, enhanced speed, and flight capabilities.
The Deep Power Stones were buried in Drood Henge, with their burial places being written in the three Drood Henge Scrolls, which were contained in special chests. The location of these scrolls are in turn documented in a special book in the royal library. The location of the first Deep Power Stone is indicated by two of the scrolls. The second Deep Power Stone is located in the same place as the Drood Henge Scroll from the purple chest.
In the past, the King left a recording on Nicole in which he explained what the Deep Power Stones were and how to find them. However, the King's file about the Deep Power Stones were time locked so that Sally could not access it until she came of age.
In 3235, Sally tried to ask Nicole about the Deep Power Stones after learning that Dr. Robotnik was looking for them so he could use them to power his Doomsday Project, but the King's time lock kept her from accessing that information, which she was first eligible for in two years. Sonic, however, managed to convince Nicole to play the King's recording of the Deep Power Stones. At the same time, Dr. Robotnik's forces managed to excavate the first Deep Power Stone at Drood Henge after finding two of the Drood Henge Scrolls. In the meantime, Rotor prepared a near-identical replica of one of the Deep Power Stones for Sonic and his friends. Using this replica, Sonic and Tails were able to convince Dr. Robotnik that they had found the second Deep Power Stone when they pretended to dig it up. Sonic proceeded to flee from Drood Henge with the replica, thereby luring Robotnik away from Drood Henge. He soon after threw the Deep Power Stone replica into a lava geyser, thus tricking Robotnik into thinking that the second Deep Power Stone was gone. Later, Sonic dug up the real second Deep Power Stone, which Sally put in his backpack for safekeeping.
At the night of the Doomsday Project, the Knothole Freedom Fighters decided to use both Deep Power Stones to destroy the Dommsday Machine and abort the Doomsday Project. To this end, Sonic went to Robotropolis, which was completely deserted, with Nicole. Led by Nicole, Sonic found the first Deep Power Stone which Robotnik kept in his headquarters. Making it to the Doomsday Machine's main generator afterward, Sonic and Sally pulled out the Deep Power Stones, planning to use their power. Robotnik and Snively soon detected them though and sent Swat-Bots to recover the Deep Power Stones. In the end, Sonic and Sally decided to use them in spite of the risks Nicole had informed them about. Empowered by the Deep Power Stones, Sonic and Sally gained incredible strength and speed, which allowed them to destroy the Doomsday Machine and defeat Dr. Robotnik, who was lost in the process. After the Doomsday Machine and its area were wiped out of existence, the Deep Power Stones disappeared, leaving behind only Sonic and Sally with energized bodies. When the duo high-fived, they felt a surge of power. Sally then wanted to see what would happen when she kissed Sonic under the influence of this power, but Sonic fled back to Knothole Village. When the pair later kissed in the village, they began to emit waves of harmless energy all around.