The Keys of Heaven are devices created by the Nexus host Teraph to fight Kronos.
There was originally a single Key: it was used to hide in a different dimension the weapon that Zeus used to kill Kronos, since it was powerful enough to destry an entire universe.
The key has been split into three parts, all of which are equally powerful.
IRON KEY OF HEAVEN
Discovered by Noriko Null on Lampyria. It was later used to forge the StarScourge; while it can no longer be used for its original scope, it can still be combined with the others.
First appearance: BTI 317
SILVER KEY OF HEAVEN
Zeus left the Key to his mother Rhea, who decided to hide it between her breasts.
Recovered first by Ilithyia and later by Noriko Null, it was later used to forge the StarScourge; while it can no longer be used for its original scope, it can still be combined with the others.
First appearance: BTI 324
GOLDEN KEY OF HEAVEN
The last Key was hidden inside the Palladium; first kept in Troy, it was later brought to Earth where it hid the planet from the rest of the Galaxy for thousands of years.
The Key has now been extracted and remains in the joint possession of Noriko Null and the Global Defense Organization.
First appearance (as the Palladium): BTI 077
First appearance (true form): BTI 456
Abilities
INDIVIDUAL KEYS
A single Key is able to teleport matter across astronomical distances: both Noriko Null and Ilithyia have used one to move an entire planet into another Galaxy.
The Keys have also been used to access the Null Zone.
COMBINED KEYS
The three Keys can be combined into a single component. This is necessary to access an otherwise inaccessible dimension.