4. The Power Stone (Orb)
The plot MacGuffin of 2014's Guardians of the Galaxy was a mysterious orb multiple parties are seeking. From Ronan the Accuser (Lee Pace) and Thanos to The Collector and The Broker, even the heroes (Gamora, Star-Lord, and Yondu) battle amongst themselves for the orb which we learn throughout the film is actually a shell housing the purple Power Stone - an ingot so powerful it can destroy a world with just a touch.
The Guardians of the Galaxy rally together, with the help of the Ravagers and Nova Corps forces, to prevent Ronan from using the stone against the planet Xandar and decide to do the right thing by giving the Power Stone to the Nova Corps for protection. It remains at Nova HQ on the planet Xandar.
This means Thanos and/or his forces will likely attack Xandar in Avengers: Infinity War, and assuming they succeed, could lay waste to the planet and Nova Corps which would offer the needed setup for Marvel Studios introducing the superhero we know as Nova from the comics - a character that Guardians of the Galaxy writer-director James Gunn revealed was considered for Marvel Phase 4.
5. The Time Stone
2016’s Doctor Strange introduces the Eye of Agamotto and with it, the secretive world of magic and mysticism. Sanctum Sanctorums around Earth protect it from supernatural threats and this mysterious faction of sorcerers was founded by Agamotto who’s yet to be explained in the films. Along with Agamotto’s teachings he left behind an artifact housing the Time Infinity Stone, meaning there were not one, but at least two Stones already here on Earth for a lengthy period of time (the other being the Tesseract).
The question of why the Stones keep finding there way to Earth and what makes our planet (known as “Terra” throughout the galaxy or Midgard across the Nine Realms) remains one of the biggest unanswered mysteries of the MCU.
By the end of Doctor Strange, Stephen Strange has become the new Sorcerer Supreme and he leaves the Eye of Agamotto where it was housed all along, but can still access it whenever he needs. This artifact provides Marvel with arguably the most interesting plot device to use in Avengers: Infinity War the untitled Avengers 4 as it wraps up the MCU as we know it. Expect there to be some time-travel!
- Spider-Man: Far From Home (2019) release date: Jul 02, 2019
- Thor: Ragnarok (2017) release date: Nov 03, 2017
- Avengers: Infinity War / The Avengers 3 (2018) release date: Apr 27, 2018
- The Avengers 4 / Avengers: Endgame (2019) release date: Apr 26, 2019
- Ant-Man & The Wasp (2018) release date: Jul 06, 2018
- Captain Marvel (2019) release date: Mar 08, 2019
- Black Panther (2018) release date: Feb 16, 2018