“Before creation itself, there were six singularities. Then the universe exploded into existence, and the remnants of these systems were forged into concentrated ingots… Infinity Stones.” — The Collector, Guardians of the Galaxy

After their creation thousands of years ago, the six Infinity Stones were scattered across the universe. Each of these stones contains a different aspect of the universe — space, mind, reality, power, time, and soul. For the longest time, these stones played an essential part in the Marvel Cinematic Universe (MCU). In Avengers: Infinity War, it is the goal of the mad titan known as Thanos to collect all six of these stones, and combine them with his infinity gauntlet. Once all the ingots have been obtained, it will give him the power to wipe out half the universe with just a snap of his fingers. Even though the stones are the main focus of Infinity War, they have been featured in seven movies prior, and it can be difficult to keep track of them all, especially if you haven’t seen all the movies. However, not everyone has time to watch seven movies in a short span of two weeks. Continue reading below for a crash course on the each of the Infinity Stones, and everything you need to know about them before the release of Avengers: Infinity War.

The first of the Infinity Stones to make an appearance is the Space Stone, debuting in 2011’s Captain America: The First Avenger. However, when it was first introduced it was known as the Tesseract, a cube shaped structure that made the user capable of controlling space itself. It allowed for the creation of portals and wormholes throughout the universe, and many have attempted to abuse its powers for evil. In 1942, during World War II, the Nazi group known as Hydra found and attempted to use the Tesseract to create powerful new weapons that could obliterate millions of lives. Before they could launch them however, they were stopped by Captain America, and the artifact fell into the Arctic Ocean, along with the star spangled soldier. It was later recovered by Howard Stark and studied for the next 70 years.

Fast forward 70 years, when Thanos begins his hunt for the stones, it is revealed that the Tesseract holds the space stone inside of it. Thanos hired Thor’s brother Loki, the God of Mischief, equipped him with a unique scepter, and sent him to retrieve the Tesseract from Earth. In return, the God of Mischief could use the stone’s powers and Thanos’ army to destroy the planet. He was stopped by the Avengers, and the stone was handed over to Thor’s homeworld of Asgard for safe keeping. It hasn’t played a significant role for quite some time, until recently in 2017’s Thor: Ragnarok, where Loki was shown grabbing the Tesseract before fleeing their crumbling home. Throughout that movie, Loki was shown to possibly have had a change of heart, so what he chooses to do with the artifact in Avengers: Infinity War remains a mystery. It doesn’t look good though, as a scene from one of the trailers showcases him handing over the cube to a darker, much larger figure.

The Mind Stone made its first appearance in the form of the scepter Thanos entrusted Loki with. Using this stone, Loki was able to use its powers to greatly enhance his mental abilities, subjugate the minds of others to his will, and project his conscience into a higher plane of existence. After Loki’s defeat, the organization known as S.H.I.E.L.D. confiscated the scepter, and attempted to keep its powers safe from evil influence. But despite their best efforts, it was discovered many years later that the terrorist organization, Hydra, had compromised S.H.I.E.L.D. and was using the scepter in various experiments, including infusing two Sokovian twins, Wanda and Pietro Maximoff, with superpowers. But even then, the Mind Stone’s full powers and capabilities were yet to be fully displayed.

In 2015’s Avengers: Age of Ultron, Tony Stark used the scepter to accidentally create an evil A.I. known as Ultron. Ultron then stole the scepter, broke the Mind Stone out of its casing, and attempted to create the perfect body for himself, but was stopped when the Avengers stole the body before it could be completed. Once in their custody, the Avengers decided to grant the body new life using the Mind Stone, which was now embedded in its forehead. This being became known as Vision, and he fought alongside the Avengers to defeat Ultron, using the powers the stone had granted him. These included the power of flight, intangibility, and the ability to shoot a high concentration beam of energy out of the stone in his forehead. Since the stone is still embedded in Vision’s head, Thanos will obviously have to remove it in order to add it to his gauntlet. Whether or not Vision can survive this process remains a mystery, but a shot in the Avengers: Infinity War trailer shows Vision being pinned on the ground by a figure while it forcefully pries the stone from his head, with Vision screaming in agony.

The third Infinity Stone to make an appearance is the Reality Stone, appearing as The Aether in 2013’s Thor: The Dark World. The Aether is a dark red liquid capable of being absorbed into one’s body. Once the host has absorbed the Aether, they are given the power to warp reality at will, granting them massive power over the universe. The Aether was discovered by Thor’s girlfriend, Jane Foster, but was reclaimed by the evil dark elf, Malekith. Eventually Malekith was destroyed, and the good people of Asgard were able to take back the substance. However, they deemed it too dangerous to keep two Infinity Stones so close together on Asgard (the other being the Space Stone in the Tesseract). Thus, the Aether was relocated to one known as Tanleer Tivan, The Collector, who promised to keep it safe. As of now, the Reality Stone still sits safely in the form of The Aether, inside the Collector’s Museum. Many of the stone’s powers are still vague and unknown, and what abilities the Reality Stone will grant the Mad Titan are yet to be discovered.

The Power Stone made its debut in 2014’s Guardians of the Galaxy, and was the central plot point of the movie. When one uses this stone’s powers, their physical abilities are greatly enhanced, and have the ability to freely manipulate energy. When used at full potential, the stone has enough power to obliterate entire planets at ease. However, not anyone can wield power like that. Like Thanos, they must be greater than just a mortal, otherwise the energy will destroy them. When Thanos learned that the stone was in an orb on the abandoned planet of Morag, he tasked Ronan the Accuser to retrieve it. In exchange for his services, Thanos agreed to use the stone’s power to wipe out Ronan’s enemy planet, Xandar. However, the space outlaw known as Star-Lord intercepted the orb before Ronan could retrieve it and took it for himself. Thanos then sent his daughter Gamora to steal the orb back from Star-Lord, but she was then attacked by Rocket Raccoon and Groot. Eventually, they all went to prison, where they met Drax the Destroyer.

After learning of the orb’s true power, they all made an agreement to escape the prison and sell the orb to The Collector, who explained to them what exactly the Infinity Stones are. But, before he could pay them for the orb, his slave grabbed the stone in an attempt to retaliate against her master. The energy was too much for her, and it killed her, exploded the Collector’s Museum, and forced the five to flee. Ronan was then able to regain custody of the orb, and was about to use it to destroy Xandar when the five outlaws, now known as The Guardians of the Galaxy, attacked him. Together they were able to brandish the stone’s powers and use them to destroy Ronan. Afterwards, the orb was given to a Xandar group known as Nova Corp for safe keeping, and still lays in their custody. The stone isn’t going to be safe for long however, as trailers show that the Power Stone is the first Infinity Stone Thanos obtains. However, what exactly he does to Nova Corp after he obtains it still remains a mystery.

The Time Stone is the fifth and most recent Infinity Stone to be introduced in the MCU. As one might guess, it gives whoever bears it immense power over time. First seen in 2016’s Doctor Strange, the elusive green gem is currently contained within an ancient artifact known as the Eye of Agamotto, and its main wielder is none other than Doctor Stephen Strange himself. The stone is one of the most powerful artifacts in the entire MCU, giving those who harness its power the ability to control the flow of time, accelerate or reverse time on an individual object, and lock something in an infinite time loop. However, the flow of time is an extremely delicate thing, and if the wielder of the stone lacks the proper skills, it can have devastating consequences. There’s no question as to whether or not Thanos has the skills to wield the stone, but how he acquires it still remains a mystery. The people at Marvel have managed to create a rich universe that spans for over several decades, and there’s no doubt that they’ll find a creative way to use the idea of time to connect it all together.

The final Infinity Stone is the Soul Stone, and almost nothing is known about it. It is the only one of the Infinity Stones not to be showcased, or even mentioned in any of the 18 movies in the MCU, nor have any of the creators mentioned it in any interviews. All that is known about it is that it is said to be the most dangerous of all the Infinity Stones. None of this has stopped fans from speculating however, as the internet is exploding with theories as to where the stone may be hidden. Many speculate it may be hidden in the African nation of Wakanda, Iron Man or Captain America may secretly have it, or it may already be in Thanos’ possession. When it comes to terms of what powers one could possess with it, they are still completely up to speculation. Taking from the comics, many theorize that it will give Thanos the power to steal the souls of others and trap them in a special soul dimension and revitalize the souls of those lost long ago.

Avengers: Infinity War hits theaters on April 27. As a film with 10 years and 18 movies in the making, Avengers: Infinity War has already sold more presale tickets than the last seven MCU films combined. There is no doubt it will be a smashing critical success, and will go down in history with some box office records.