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Quote1.png Your gravity power don't stop you from eating! Julie's lightspeed powers don't stop her! Neither do Katie's energy powers! But me? I'm starving and clouds can't eat! Quote2.png
Jack Power (Earth-616)[src]


Brash and ornery, Jack Power was the "wild child" of the Power siblings. He frequently insulted and argued, both with his teammates and his adversaries. Queen Maraud, Power Pack's archenemy, feared him more than the other children because she thought he would be the most likely to take advantage of the lethal nature of his powers.

However, his bold nature also made him the main fighter on the team. He possessed a tremendous amount of loyalty and courage, and usually kept a cool head even during stressful situations. Jack jumped into the East River to help his sister Katie escape from an ocean liner, and even taunted the Snark Jakal who was about to kill him with "Can't even kill someone until Mommy tells you to?!"

Jack was perhaps the most innovative member of the Pack in terms of developing new power variations. When he received new powers, he was able to figure them out quickly and invent new uses for them. He was significantly better at controlling his gravity powers than Alex.

Jack retained his bold personality, and continued to develop new applications of his powers, including a "density field," but he also showed a kinder, gentler side. Jack opted to leave the team to care for his mother.[1]

Jack Power (Earth-616) from Unbelievable Gwenpool Vol 1 25 001.jpg

At some point, Mass Master briefly rejoined the Power Pack and teamed-up with Devil Dinosaur, Gwenpool, and Moon Girl.[2]



Primarily, Jack has the ability to control the density of the molecules of his body. He can disperse his molecules into a dense, cloud-like form, or reduce the space between them until he is a small, highly resistant 8" size. He has also shown the ability to materialize a portion, or just a part of

Mass Master

his body, such a his upper body while his lower half is in cloud form. During the "Peer Pressure" Miniseries, Jack revealed that he could now form density fields in the form of shields or force-fields. When his sister Julie had the powers as Molecula, she discovered that she could also assume an 8' form that was nearly intangible, but Jack has never shown this degree on control. Julie was also the first to use a force-field as a shield but Jack was more innovative in his use of the force-field as more than just a shield. As Counterweight, Jack had the gravity manipulation powers, and as Energizer, he had the energy absorption/projection powers.



  • Power Pack Uniforms: Mass Master wears a special costume made of unstable molecules by the Kymellian Smartship Friday.The costume shrinks and expands in size as Mass Master does, and turns gaseous and solid when he does.


The team usually rely on the Kymellian Smartship Friday.


  • Jack is a member of the Forums social media network.[3]

See Also

Links and References


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