Dominus Librium

The Dominus Librium is an ancient artifact believed to be of alien origin. It has the power to absorb the power of others.

Ben 10 Alien Force
It was hidden on a remote island, protected by a gauntlet of traps and stone monsters but Kevin and Darkstar were able to steal it and escape and later both used it remove their powers and mutated appearances. Afterwards, Darkstar stole the artifact from Kevin and fled.

Darkstar used the Dominus Librium on Gwen when he stole her energy and magical powers returning her to a zombie like state, similar to the first time it happened. The Librium also took the powers of Swampfire as well.

While the energies of Gwen and Swampfire were being absorbed, Kevin grabbed ahold of the artifact, which caused it to overload and explode, breaking into three pieces, the two larger pieces on the other end which were presumably destroyed by Kevin and the smaller piece with a face on it that was attached to Darkstar's clothing. After the Librium was destroyed, Darkstar's and Kevin's forms reverted back to their mutated appearance and regained their powers.

Ben 10 Ultimate Alien
Darkstar revealed to have kept a fragment of the Dominus Librium after it was destroyed, though it was no longer useful. Fortunately, it would only be useful when given a powerful energy surge. Therefore, Cooper Daniels and Darkstar went to built a machine to revert Kevin back to his original form but then he betrayed ben and the rest but was unsecessful

When Kevin reverted to his human form, Darkstar took advantage of this moment and absorbed the powers that was taken by the Dominus Librium. However, Ben anticipated this plot all along and hit a button which had canceled out Darkstar's newfound power, and all the abilities were returned to their rightful owners, including the resurrection of the five Andromeda Aliens.

Powers and Abilities
It was originally used to cancel out the effective super powers of two individuals. This would be done by having the two beings hold each side of the Librium and have their energy/power cancel each others out.

Weaknesses
The Dominus Librium is known to be very sensitive when absorbing the powers of others, this is the only reason why Kevin was able to stop it, but since he grabbed it,it took the energy of Gwen and the Omnitrix from Darkstar and transferred it into Kevin (Mainly the Omnitrix energy went into Kevin) and when he ripped off both sides of the librium which overloaded it and caused it to explode which made Darkstar back to the way he was and Kevin back to the way he was (by absorbing the omnitrix energy). Also, the artifact takes rather long to absorb the powers of other, this may be normal or that its victims may have just had a lot of power to absorb.

Alien Force

 * Trade-Off (first appearance)

Ultimate Alien

 * Absolute Power: Part 1 (first re-appearance)
 * Absolute Power: Part 2

Trivia

 * The Dominus Librium was used by Darkstar to replace his original power. Though it did give him a more advanced and better version.
 * It will work on any lifeforms shown in the episode it was premeriered in.
 * To players of The Legend of Zelda Twilight Princess this may look similar to Midna's headgear.
 * The name comes from the latin word "domine", meaning "lord", and "librium", as in "equilibrium", the sense of balance. Roughly translated, it means "Lord of Balance".