The Time Stone grants the user the ability to control time itself, slow down, speed up, stop, or create loops. It also allows for control of the aging process, allowing the user to speed it up or reverse it. At the most basic levels, it allows visions of the future or the past. At the higher tiers of power, the user can create time loops trapping enemies or circumventing entropy allowing things to exist in pristine condition indefinitely. The highest possible power allows the user to exist at all times simultaneously.
In the comic books it was originally created when Nemesis destroyed itself. The Elders of the Universe bound all the Stones together in order to try to defeat Galactus. However, when the Elders ultimately fell, the Time Stone resided with the Gardener. Thanos eventually obtained the Time Stone during his conquest to obtain all the Infinity Stones, leading to the Infinity Wars.
In the Marvel Cinematic Universe (MCU) the Time Stone has yet to be introduced. The main problem with the Time Stone is the ridiculous amount of power the stone grants. I would argue it is the most powerful standalone stone out of the six. Not to mention the stone just randomly disappears constantly in the comic books. When they finally introduce it into the MCU, it is going to be interesting to see how unpredictable they make the stone. As for where it could be in the MCU, my hypothesis is it is nowhere right now. The stone has the tendency to disappear and reappear somewhen else in time. I suspect it just doesn’t exist at this point in time and that it will appear at a later date.
Another bit of speculation is based around the Infinity Stones spelling out the name T-H-A-N-O-S. This easter egg leads us to the Time Stone being represented as something starting with the letter ‘N’ or ‘H’. While this doesn’t do much for us since it is not nearly specific enough to base any educated guess on, I think it is something to keep in mind as we move forward. When we get a glimpse at some incredibly powerful artifact that starts with the letter ‘N’ or ‘H’ we should be suspicious as to whether it is a Stone. This is more than likely the last Stone we will see in the MCU and because of that is probably 2-3 years away. If this is the case, then we have 2-3 years to speculate on where and when is the Time Stone.
***As the MCU progresses this page will be updated***