Energy Stone

Energy Stones are mysterious stones that are able to store regalia used by Blades contain Regalia. By releasing the power of the stone, a Blade can absorb its power and use the regalia stored inside. If a regalia is stored in an Energy Stone, they cannot be used by its original owner, unless they release the stone.

There are 4 types of Energy Stones, differing in the amount of energy they can store.

Releasing an Energy Stone's Power
An energy stone can only be released if the Blade's power exceeds that of the regalia. The only exception to this rule is releasing a Black Energy Stone. These stones, have separate restrictions to releasing them than other stones.

Upon releasing the Stone, a circular scar will appear on the Blade's body. The scar appears on a random spot on the body and cannot overlap with another scar from an Energy Stone.

There is no limit to the amount of stones a person can release, or a limit to the amount of regalia at one Blade's disposal.

Blue
Blue Energy Stones are the weakest of the four types of Energy Stones. The weapons that these can hold are weak, however their availability is quite common. They can only hold C ranked regalia.

Red
Red Energy Stones are the second weakest of the four types of Energy Stones. The weapons that these can hold are stronger than those in Blue Energy Stones, however they are still rather weak. They can only hold B or C ranked regalia.

White
White Energy Stones are the second strongest of the four types of Energy Stones. The regalia that these stones can hold are very powerful and include all but the Legendary Regalia which are reserved for the Black Energy Stones.

Black
Black Energy Stones are the most powerful of the four types of Energy Stones. These stones can hold the Legendary Regalia. Unlike the other stones that require the user to have sufficient power to use the weapons contained within them, the Black stones only allow access to the weapon inside if the user is worthy, a criteria that ignores relative power of the user.

In addition, Black Energy Stones are the only Energy Stones that can hold more than one regalia at once, although this does not apply to the Legendary Regalia as their power is still too massive to be paired with another inside one stone.