Avengers: Infinity War will be the biggest blockbuster to hit the screen this decade. It features the Mad Titan Thanos finally confronting the Avengers in his quest for the Infinity Stones. This is a film that's been 10 years in the making through other smaller franchises. Iron Man, Captain America, Thor, and Hulk and so many others will face their ultimate test and it's looking more and more likely that some of them will not survive. Joe Russo, co-director of Infinity War, has stated that the film will be the "final chapter" of the story Marvel's been writing since Iron Man.

There are so many artifacts in the MCU that have been mentioned, but the key objects of all four phases have been the Infinity Stones. The first one appeared in Captain America: The First Avenger (though we didn't know it at the time) and the others have been popping up ever since. Now, the Infinity War trailer has shown us that Thanos will use the Infinity Gauntlet to bring a reckoning to Earth and the larger universe. With all the mystery and terror surrounding the Infinity Stones, we wanted to give you some more background on the weirder facts that we know about them in the MCU. We dug deep and this is what we found.

15 FORMED INTO STONES WHEN UNIVERSE STARTED

The Infinity Stones have been in the MCU since Captain America: The First Avenger, but weren't given that name until they were mentioned as such in Guardians of the Galaxy. Thor then mentioned them from his vision in Avengers: Age of Ultron. He talks about the destructive power of the Infinity Stones and how the stone on Vision's forehead is only one of six.

The information is limited, but in Guardians of the Galaxy we are given a detailed account of their history. The Collector mentions there were six singularities before creation and were compressed into six trinkets when the universe began. They were known as Infinity Stones. Unfortunately, not much is known about why the singularities were compressed into Infinity Stones, but their awesome power compressed into stones make them universe-ending objects.

14 CAN ONLY BE WIELDED BY A SELECT FEW

During the Collector's oral history of the Infinity Stones, he mentions that only powerful beings can withstand their raw power. From the few times we've seen the stones handled by mere mortals, the stones have effectively destroyed them or disposed of them in some other way. When Red Skull tried to handle the Tesseract, it ended up teleporting him somewhere far or possibly destroying him despite the Space Stone's casing.

In Guardians of the Galaxy, one of the Collector's slaves grabbed the Power Stone hoping it would be the key to her freedom. Unfortunately, the Power Stone was too great for her to possess and it killed her almost instantaneously. The Aether, or Reality Stone, also nearly killed Jane Foster in Thor: The Dark World, but the energy coursing through her body was removed by Malekith for his own evil plans.

13 USED TO COMMIT GENOCIDES BY THE CELESTIALS

Since only beings of immense power can harbor the stones, it is interesting to note the god-like tendencies the Celestials took on when they were in possession of the Orb which held the Power Stone. The Collector mentions how they used the Power Stone to cast judgment on whole planets and their civilizations. They decided to commit genocides if they felt those civilizations weren't worthy of existence.

This is a reminder of how the Infinity  Stones are used by beings who are extremely powerful. When Ronan the Accuser, decided to destroy Xandar for their crimes, he wanted to use the Power Stone to obliterate them. Also, Thanos wants to use the Infinity Gauntlet to bring "balance to the universe," which sounds like a whole lot of killing, considering the Infinity War trailer.

12 MIND STONE GAVE SCARLET WITCH AND QUICKSILVER POWERS

When the Tesseract was placed in the care of Asgard, the scepter Loki used during Avengers was somehow stolen by Hydra. It came into the possession of Baron Wolfgang von Strucker, the current Hydra leader. He, along with Doctor List, started experimenting on volunteers at their base in Sokovia. This led to the death of many people... except for two.

Wanda and Pietro Maximoff both received their powers through the experiments performed with the scepter which housed the Mind Stone. It is an interesting thing to note that the Mind Stone granted them powers as we've only seen it used for energy blasts and mind control. It makes us wonder what other functions the Mind Stone has and how Thanos will use it to commit his balancing of the MCU.

11 MIND STONE GAVE ULTRON AND VISION LIFE

During Avengers: Age of Ultron, Tony Stark decided that he needed to create an artificially intelligent system that would protect the planet from threats coming from outer space. He meant for the Ultron program to be a  "suit of armor" around the world by using the power of the scepter, which housed the Mind Stone. Tony instead created the world's next biggest threat in Ultron.

Ultron used the Mind Stone along with scientist Helen Cho's help to create a new and more powerful body for himself. Before he could upload his consciousness into the body, it was taken away by the Avengers. Tony and Bruce Banner then uploaded JARVIS into the body which along with the Mind Stone created the Vision. The Mind Stone has also given Vision some more human qualities as the films have progressed. He feels love for Scarlet Witch and guilt for nearly killing War Machine.

10 HYDRA WEAPONIZED THE SPACE STONE

In Captain America: The First Avenger, we got our first glimpse at the destructive power of the Space Stone when it fell into the hands of the Red Skull. The Space Stone, housed by the Tesseract, was used to create weapons of mass destruction, so Hydra could take over the world. Dr. Zola helped the Red Skull create conductors that would use the energy in the Tesseract offensively.

The Tesseract was eventually lost during the final scene of The First Avenger, but it was recovered later by an early version of S.H.I.E.L.D. Ironically, Nick Fury decided to use the Tesseract to create new weapons to fight against otherworldly forces that wanted to harm Earth such as the Destroyer from Thor did. This was a move by S.H.I.E.L.D. that was overwhelmingly opposed by the Avengers.

9 SPACE STONE TELEPORT REMOTELY

The Space Stone has the ability to manipulate space to make travel easy for whomever uses it. It is possibly what happened to Red Skull when he interacted with the Tesseract directly. He was most likely teleported somewhere against his wishes because he wasn't powerful enough to harbor the energy of the Space Stone held within.

In Marvel's the Avengers, Thanos managed to pull off something we didn't realize was possible at the time. He tapped into the power of the Space Stone to teleport Loki directly to the Tesseract's location. It's unclear whether or not all of the Infinity Stones can be accessed indirectly in this manner, but it does set a dangerous precedent for the Avengers if Thanos possesses this knowledge going into Infinity War.

8 HEIMDALL POSSESSED THE SPACE STONE

Most fans of the MCU don't know that a lot of things are actually happening in comic book tie-ins that Marvel makes to bridge the storytelling gap between films. In Thor: The Dark World Prelude, they address how and why the Tesseract, harboring the Space Stone, ended up on Asgard after the battle of New York against the Chitauri. One reason was that the Avengers thought having two Infinity Stones on Earth was too big of a risk.

That wasn't the only reason why Asgard took possession of the Space Stone. When it was given to Heimdall, he needed it in order to repair the damage done to the Bifrost Bridge. The damage had made it hard for Heimdall and Asgard to protect the inhabitants of the Nine Realms from the Marauders.

7 TONY'S ARC REACTOR INHIBITED THE MIND STONE

During Marvel's the Avengers, Loki possessed the scepter which housed the Mind Stone, given to him by Thanos. The Mad Titan wanted Loki to retrieve the Tesseract, so that he could retrieve another Infinity Stone for himself. Loki ended up using the Mind Stone to cause serious damage to S.H.I.E.L.D. by controlling the mind of Hawkeye and so many others.

When Loki tried to take control of Tony Stark's mind near the end of the movie, it somehow didn't put him under Loki's command. Tony then remarked that "performance issues" might be the cause, but every time Loki pressed the scepter to Tony's chest, it clinked against his arc reactor. It somehow saved Tony from being put under Loki's spell. Thank goodness it did because another Avenger under Loki's control would've probably won him the invasion, especially Iron Man.

6 REALITY STONE WOKE MALEKITH AND HIS DARK ELVES

When Jane Foster went to an abandoned warehouse to examine strange anomalies that were popping up around Earth in Thor: The Dark World, she ended up coming into contact with the Reality Stone. That contact somehow woke up Malekith and his Dark Elves on a ship where they were in a deep sleep for thousands of years. It wasn't just them that woke up though, their ship also powered up in that moment.

Malekith and the Dark Elves originally had the Aether, aka the Reality Stone, in their possession and meant to destroy the Nine Realms with it. Luckily, they were defeated by Asgard before they could. Malekith, in a last-ditch effort to kill as many Asgardians as he could, destroyed the other elves there, including his wife and son, and put him and his small group of followers into hibernation.

5 MALEKITH USED THE REALITY STONE TO TELEPORT (AND MORE)

We've only seen the Infinity Stones in action a few times. One of them was during Thor: The Dark World, when Malekith was awakened by the Reality Stone from his deep hibernation. He felt its power across the universe. His age-old plan to destroy the Nine Realms resurfaced and he found the Aether again. He nearly completed his genocidal task before he was stopped by Thor.

Malekith and Thor battled it out, but the Dark Elf had a few tricks up his sleeve. He used the power of the Reality Stone to create tendrils that would attack Thor on his command. Malekith was also able to teleport with it to dodge any of Thor's attacks. He also used the Aether to create a red tornado-like weapon that would destroy the Nine Realms during the Convergence.

4 MAGIC ACTIVATES THE TIME STONE

The Infinity Stones have been used by extremely powerful beings such as Thanos and other Celestials, but the power of an Infinity Stone can be accessed and utilized through Eldritch Magic. In Doctor Strange, Stephen discovers the existence of the Eye of Agamotto in a book from the Ancient One's private collection and decides to test its power on an apple.

However, the only way Strange can use the Eye of Agamotto is through the power of magic. We've seen that Infinity Stones have been put inside other objects like the Loki's scepter and the Tesseract. The Eye of Agamotto is similar, but instead of anybody being able to use it, only a mystic with the power to harness the Eye can utilize its potential... so far.

3 THE REALITY STONE CAN BECOME SHAPELESS

In Thor: The Dark World, we are introduced to something called the Aether. Jane Foster ends up coming into direct contact with it in a dimension Heimdall cannot see. The first time we see the Aether, which is the Reality Stone, we see it as this shapeless and temperamental object that was hidden away by Bor and the Asgardians when they took it from the Dark Elves millennia ago.

When the Collector gives us a concise history of the Infinity Stones, it was originally shaped much like the others. It didn't have the liquid properties that it exhibited in The Dark World. However, it did still have its famous red color. Its shapelessness is a quality that makes this Infinity Stone more unique than the others.

2 REALITY STONE INFECTS HUMANS

The Reality Stone is a strange one. We've seen it used by the Dark Elves to create a Convergence that would destroy all the Nine Realms and we've also seen it do something else that's peculiar. When Jane Foster and her team go to an abandoned warehouse in search of portals, she finds herself in a dimension where the Reality Stone was hidden thousands of years ago.

It infects her with its energy and when a police officer touches her shoulder to arrest her, a projection of energy explodes from her body. The energy from the Reality Stone has given her a strange illness. The healers of Asgard can't seem to figure out what it is, but Odin knows what infected her. Thankfully, Malekith later steals the energy from Foster in the film and cures her.

1 THE SOUL STONE THE BIGGEST THREAT TO THE MCU

We don't know much about the Soul Stone. It is the only Infinity Stone that hasn't made an appearance in any of the movies (not counting seeing it in Guardians of the Galaxy during the Collector's oral history of them). We still don't know where it is or exactly what it does in the MCU. However, we do know that it's possibly orange. We also know that it's the biggest threat lurking in the entire MCU.

In Avengers: Infinity War Prelude, Wong interrupts Strange because he senses there is a cosmic imbalance occurring. He proceeds to explain the history of each Infinity Stone before they are interrupted by Thor and Loki when they arrive in NYC during Thor:Ragnorok. When Strange returns, Wong tells him that he knows little about the Soul Stone, but according to the ancient texts, it could prove to be the "biggest threat of them all."