The Coffer of Shadow is an ancient artifact of immense power. It is an ornate box made of lead in the form of the God Baphomet. The Coffer has been in the possession of the Coven of Shadows for over 1000 years. It is the symbolic seat of power and is always held by the High Priest or High Priestess of the coven. The High Priest/ess is always the strongest member of the coven and a Master of the Mystic Arts commanding the Power of Shadow.
The shadow in the Coffer of Shadow refers to the combined energy of every current and past member of the coven. When a new member is initiated into the Coven of Shadows his or her blood is ritually spilled onto the Coffer of Shadow. Thereafter that individual's strength, energy, and knowledge is added to the pool of power contained within. The High Priest/ess of the Coven commands this power, wielding it as he or she sees fit.
The last holder of the Coffer of Shadow was a wicked sorceress named Selena Lionheart. Through a series of events which I am unclear about myself, Selena came into possession of a piece of alien technology in the form of a crystalline sphere. It was later identified as an omegahedron by Supergirl who had come from another dimension to retrieve the mystery ball. The omegahedron was a power-source vital to her home-world, but in Selena's hands it became a powerful force of magic. Selena placed the omegahedron in the Coffer of Shadow exponentially increasing her power.
Selena became aware of Supergirl's existence on Earth when the heroine interfered in her plans to seduce Ethan, a local landscaper. Selena tricked Ethan to her fun-house, where she lived, with the prospect of hiring him as a landscaper. She secretly fed Ethan a love potion which rendered him unconscious and he wandered away while Selena was temporarily distracted. Selena scryed out his location in her magic mirror and called upon the power of shadow to bring him back. The spell animated a nearby bulldozer which pursued Ethan. After tearing apart a portion of the business district along Main Street the bulldozer captured Ethan inside its jaws.
A bystander interfered with the spell by climbing inside the bulldozer in attempt to bring its path of destruction to an end, which caused Selena to lose control of the bulldozer. Selena and her cohort Bianca watched as Supergirl appeared out of seemingly nowhere to save the bystanders from the effects of the bulldozer's rampage. Once Supergirl secured the scene, she removed the jaws of the bulldozer to a safe location and freed Ethan.
Upon awakening from his potion-induced stupor, Ethan laid eyes on Linda Lee and subsequently fell in love with her. Enraged, Selena called upon the power of shadow to take the form of a destructive invisible force to destroy Linda. Supergirl interfered and, after a brief but hard-fought battle, defeated Selena's demonic creation. It was then that Selena made a shocking discovery... the omegahedron had a strange and unexpected effect on the Coffer of Shadow. Much like Selena's over-reaching ambition, the coffer had grown bigger and uglier! As Selena's hunger for power grew the coffer continued to grow and morph into a simulacrum of Selena's evil.
Supergirl somehow tracked Selena to the abandoned fun-house where the two women confronted one another. For some unknown reason, Ethan was present as well. Rather than continue her battle with Selena, whose powers were growing by leaps and bounds, Supergirl chose to remove Ethan to a safe location.
Desperate to defeat her enemy and master her newfound powers Selena called upon me for assistance. Desiring to be close to such power, and perhaps taking it for myself, I decided to attempt to use the Coffer of Shadow in conjunction with my Burundi Wand. Selena and I were successful in teleporting Ethan back to the fun-house in hopes that Supergirl would come to save him and fall into our trap. I didn't trust Selena completely, but little did I know that she would betray me so soon. In a moment of passion, she snatched the Burundi Wand out of my hands and turned its power on me. Weak and helpless I could only stand by as she transformed her home into a castle stronghold high atop a mountain in the center of town.
When Supergirl arrived to save Ethan, Selena cleverly banished Supergirl to a dimension where her powers abandoned her. With Supergirl trapped in the Phantom Zone and Superman on a diplomatic mission in a galaxy several hundred trillion light years away there was no one to oppose Selena's will. She quickly overtook the town and intended to expand her power until she had achieved nothing less than world domination.
Before Selena could achieve her dream Supergirl found a way out of the Phantom Zone and returned to Earth with her powers restored. Supergirl confronted Selena who called upon the full power of the Coffer of Shadow which had grown to gigantic proportions. Supergirl fought Selena's evil creation and would surely have been defeated had Ethan not been able to sever Selena's connection to her power-source. Supergirl used the opportunity to sweep Selena, Bianca, and her monstrous creation into the Phantom Zone and sealed the portal between dimensions.
After Selena's defeat everything returned to normal, including the Coffer of Shadow. I found the Coffer, in its original form, lying in the road where Selena's fortress once stood high atop what came to be affectionately known as Mount Midvale. Knowing the Coffer's value and history, I took it with me. Soon thereafter, I was approached by Sandy Dixon a pretty young lady who had been one of Selena's followers. Sandy became my apprentice and it was through her that Selena's coven learned that I assisted in Selena's defeat and that I now held the Coffer of Shadow. The coven saw this as a clear sign that I should now be their new High Priest and I accepted the position.
Since that time I have discovered that a portion of the omegahedron's power continues to reside within the Coffer of Shadow on a molecular level. The Coffer of Shadow simply IS power, and it is capable of all manner of sorceries....