An immensely powerful object/being published in the comics of Marvel Comics.

The Cosmic Cube is one of a number of creations of the extra-dimensional race called the Beyonders. The Beyonders are partly responsible for the creation of the Savage Land and one of their race was the instigator of both of the Marvel limited series Secret Wars and Secret Wars II. The Beyonders are incredibly powerful beings with seemingly infinite power. They have had contact with races from our dimension for many centuries. Part of that contact is to allow individual races to use their scientific knowledge to breach the walls between their universe and ours, releasing a sentient energy field which collects itself in the form of a perfect cube. These cubes are the immature stage of this life form that later takes on a form similar, but not totally the same as the race that created it.

The Cosmic Cubes, as they are called, possess the ability to reshape reality to the wishes of the individual that is holding it. According to the scope and size of the change determines whether or not the change is permanent.

The first Cosmic Cube that we are aware of was created by Skrull scientists many centuries ago. The Cube eventually matured but due to the uncontrolled nature of its maturation, it caused untold damage through out the area in which the Skrulls lived. Entire solar systems were destroyed and the Skrull civilization was thrown into such chaos that they have taken years to recover. This Skrull Cube took the name the Shaper of Worlds and had the appearance of a giant blue Skrull torso atop a platform with a tank tread. The Shaper used its powers to give people their fondest wishes in an attempt to make up for the harm it originally did.

The second Cosmic Cube was created by an off-shoot of the criminal organization HYDRA, known as A.I.M. or Advanced Idea Mechanics. A.I.M. created the Cube through the use of an scientifically enhanced member of the organization, called MODOK. A piece of the Cube was used by A.I.M. to give one of their creations, the Super Adaptoid, its ability to take on the appearance and abilities of others both human and super-human. The Cube was key in many different plots by evil men to further their own power. The Cube was used by the Red Skull in his conflicts with Captain America and was key in the origin of the hero the Falcon. The Cube was also used by the mad Titan, Thanos, in his bid to take over the universe, but was thwarted by the original Captain Marvel. The Cube was also used by the evil genius Dr. Doom for a time.

Eventually, the Cube began its maturation process, but due to its contact with evil, it had been tainted and its rise to maturity would have been even more violent than the Skrull Cube, except for the intervention of the Shaper of Worlds. It cleansed the Cube of its evil taint and the Cube matured into a humaniod form and renamed itself Kubik. Kubik departed earth with the Shaper of Worlds to learn what it could of the universe.

Kubik has revisited Earth on a number of times since its departure. It has come into conflict with the Super Adaptoid who mimicked its reality shaping abilities and attempted to take over the world, but was opposed by the Avengers. Kubik removed the Adaptoid's ability to mimic others by reclaiming the sliver of itself that resided in the android.