The Marvel Universe is full of powerful forces, primal energies of creation that empower heroes and villains alike. One of the most powerful is the Phoenix Force. Tied directly to life and rebirth, the Phoenix Force gives its bearer godlike power that rivals that of any cosmic being but there's a cost, most Phoenix hosts go crazy.

RELATED: 5 DC Heroes Who Would Make Good Phoenix Hosts (& 5 Who Would Go Dark Phoenix)

Another one of these powerful forces is the Power Cosmic. One of the most powerful forces in the Marvel Universe, the cosmic titan Galactus empowers his Heralds with it, allowing them to achieve all manner of feats, some altruistic and some terrible. These two forces are both very powerful, but only one can be the most powerful. Let's take a look at the Phoenix Force and the Power Cosmic.

10 Phoenix Force: Absolute Corruption

Dark Phoenix xmen

It's said that absolute power corrupts absolutely; in the case of the Phoenix Force, this is definitely true. While not all of its hosts have gone crazy, the vast majority have. It doesn't matter if they were suited for the power or not, they usually all fall.

The Phoenix gives its bearer amazing power and most are just not ready for it. They all start able to control it, but as things go on and they realize just how powerful they are, it all starts to slip away and they become more and more detached from their humanity until they've completely lost themselves in the power.

9 Power Cosmic: The Source Of Galactus's Power

Galactus shows his power

Galactus is one of the most formidable beings in the Marvel Universe. Hailing from the universe that existed before the current one, he was forged in the crucible of the Big Bang and came out as one of the most powerful beings in creation. The fuel for all of that power is the Power Cosmic.

RELATED: 5 Marvel Cosmic Beings That Are More Powerful Than Galactus (& 5 That Aren't)

Galactus needs to devour planets for sustenance and this powers the Power Cosmic, allowing him to perform all kinds of amazing feats, ones that have made him one of the most feared beings in all of the universe. A fully powered Galactus is nearly unbeatable and even a hungry Galactus is still a foe that no one wants to face.

8 Phoenix Force: The Embodiment Of Life And Rebirth

iron fist weilded phoenix force

One of the things that set the Phoenix Force apart from other powers in comics is the fact that it's actually a being as well as a power. It's hard to say whether it's completely sentient or not but it does have a will of its own and chooses the beings it feels are best suited for its power, although accidents do happen, like with the Phoenix Five, five X-Men who accidentally got the power of the Phoenix.

The Phoenix Force has been shown acting on its own, like when it helped a group of powerful beings, many of whom were the precursors of modern heroes, destroy the Mad Celestials. The Phoenix and Odin even had a relationship during this time.

7 Power Cosmic: The Heralds

Nova, Terrax, and Silver Sirfer

Galactus, being an all-powerful being, doesn't really like to do his own dirty work. Like any powerful being, he doesn't like to have to find his own food, and that what he has his Heralds for, although that's not the only thing they are for. They travel the cosmos with him, finding him planets to devour and helping him fight his battles, defending him when he is at his weakest.

The Heralds are some of the most powerful beings in the universe, imbued with the Power Cosmic by their master. While they aren't as powerful as he is, they are more powerful than just about any being they'll find themselves up against.

6 Phoenix Force: Telepathic Titans

white phoenix of the crown

The Phoenix Force gives its hosts many powers but at the core of all of them are powerful mental abilities. Most Phoenix Hosts over the years have been mutants and once they are imbued with the power of the Phoenix, they are immediately placed among the most powerful mutants, the Omega level. They keep whatever powers they had before but also gain amazing psionic powers.

The mental abilities the Phoenix gives its host makes them more powerful than the most powerful telepaths; even Professor X can't handle a Phoenix empowered host, even if they have no prior experience with mental powers.

5 Power Cosmic: Nothing Really Matters

Cosmic Ghost Rider using the Power Cosmic

The Power Cosmic gives its bearer many powers that make them extremely hard beings to defeat but one of the greatest powers it gives is the ability to manipulate matter. A being with the Power Cosmic can transform matter from one state to another, turning solids to liquids or gases to solids and so on. They can completely transform one thing into another.

They can even manipulate organic matter. Someone with the Power Cosmic can't create life but they can do just about anything up to it.

4 Phoenix Force: The Power To Change The Natural World

Phoenix 5 X-Men

As alluded to earlier, five X-Men were given the power of the Phoenix, becoming the Phoenix Five. They immediately set out to change the world, both literally and figuratively. They began to use their powers to fix what they saw as wrong in the world, doing great deeds in order to smooth out relations between humans and mutants.

RELATED: Marvel: The 10 Worst Things The Phoenix Five Have Done

They took land that was barren and made it arable, purified water, sealed the San Andreas fault line, and more. The most impressive thing about this is that each of the Phoenix Five only possessed a fifth of the power of the Phoenix and they were able to accomplish some amazing things.

3 Power Cosmic: Where Gods Fear To Tread

Silver Surfer Vs Thor

Galactus's Heralds are known as some of the most powerful beings in the universe and there's a good reason for that. The Power Cosmic increases their strength, speed, and durability to unheard-of levels. Beyond the power to manipulate matter, it also allows them to harness and control tremendous cosmic power.

Those with the Power Cosmic have been known to fight the most powerful beings in the Marvel Universe to a standstill; heroes as powerful as Thor have found it hard to compete with them. Even gods know better than to mess with beings with the Power Cosmic.

2 Phoenix Force: Reigniting The Mutant Race

White Phoenix of the Crown

Scarlet Witch is one of the most powerful beings on the planet Earth. Able to manipulate reality, she can pretty much do whatever she wants. One day, she decided there should be no more mutants and she made it so, not only depowering most of the mutant race, but erasing the X-gene from not just the planet, but the multiverse.

Hope Summers, imbued with the full power of the Phoenix, was able to reignite the mutant race by joining its power with the Scarlet Witch's. This was a big deal because no one, not even Scarlet Witch herself, was able to undo what she had done when she uttered, "No more mutants."

1 Power Cosmic: For Good And For Evil

Silver Surfer on his surfboard in the stars

Silver Surfer is one of the Marvel Universe's greatest heroes. A pure-hearted man, he was able to prove that great power doesn't always lead one down the wrong road and set an example for future Heralds of Galactus, like Firelord and Air-Walker- that they could use their powers for good and be forces for change in the universe.

Conversely, Heralds like Terrax and Morg used their powers for evil, terrorizing the universe even beyond what their duties as Galactus's Heralds entailed. The Power Cosmic allows beings to do great things, for good or for ill.

NEXT: 5 DC Villains That Galactus Can Defeat (& 5 He Can't)