[Spoilers for Avengers: Infinity War, but c’mon]
“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.” That’s the Collector in Guardians of the Galaxy explaining the creation of the Infinity Stones: Space, Reality, Power, Mind, Time, and Soul. But besides that bit of exposition, there isn’t an official Marvel Cinematic Universe description of what the stones are capable of, outside of killing half the universe’s population (including the puppies and kitties) when combined with the Infinity Gauntlet.
Thankfully, to coincidence with the release of Avengers: Infinity War on digital and Blu-ray, Marvel has released a featurette on the powers of the Infinity Stones. (It’s more detailed than Wong telling Doctor Strange that the stones “each control an essential aspect of existence.” No offense, Wong.)
-Space Stone: “Travel across any dimension”
-Time Stone: “See the future, alter the past”
-Reality Stone: “Bend reality to your will”
-Soul Stone: “Control life and death”
-Power Stone: “Destroy anything in your path”
-Mind Stone: “Create and alter consciousness”
Thanos is a God-like interdimensional traveler who sees and controls all — no wonder he won. The definition for the Soul Stone is particularly important. It has the ability to kill, but it’s also able to resurrect, which could prove essential following the events of Infinity War, where most of our heroes died. (Maybe don’t let Star-Lord tussle with Thanos this time.) If any one stone is going to matter more than the others in Avengers 4, well, you gotta have soul.