My current theory for Avengers 4 and Dr. Strange’s plan has come down to the following points you need to pay attention to.



1. Gamora’s soul is bound to the soul stone. She was bound because she was sacrificed in exchange for the stone.



2. After The Snap, Thanos found himself at a quiet, orange colored, watery place, where he briefly speaks to Gamora as a child. This place was inside the soul stone, and it was Gamora’s soul. Note that the color fits.



3. Everyone who became dust and Gamora’s soul can be saved. Other manual deaths may be permanent.

4. Dr. Strange has seen the one possible future where the heroes succeed. Strange is planning to set up everything so that this timeline occurs.



5. Likely on Titan, Dr. Strange travels into the past via the Time Gem and recruits Heimdall, The Hulk and possibly Loki.

6a. The Hulk is crucial for the victory timeline, and he must do something at the right moment. For this reason, Heimdall sacrificed himself to send Hulk back to Earth, and Hulk refuses to show himself until the time is right. If Loki was recruited as well, his job was to ensure Thor’s survival, because he is crucial for the victory timeline.



6b. Note that Dr. Strange had Heimdall send Hulk to himself on Earth, so Strange knew beforehand that someone had sent Hulk, and he may have realized later that it was himself. This is how he knew what to do.



7. Dr. Strange sacrifices the Time Gem at to correct moment to save Tony, because Tony is required for the victory timeline, saying to Tony: “It was the only way.”



8. Furthering point 7, all the major technicians (Rocket, Tony, Bruce, Shuri) are still around. They may be required to combine their brilliance in order to beat Thanos.

9. For each infinity stone, a character sacrificed themselves or someone they loved, at least attempting to do so. These sacrifices usually happened in the presence of a particular stone. It may be that these sacrifices make different characters the real masters of the stones.



Power Gem: Groot sacrifices himself out of love (Guardians vol. 1)

Space Gem: Loki for Thor

Reality Gem: Quill -> Gamora (attempted in presence of the gem)

Soul Gem: Gamora -> herself (for Nebula, but not in presence of the gem)

Mind Gem: Wanda -> Vision

Time Gem: Strange -> unclear at this point (maybe himself & his duty)



Even with Dr. Strange’s sacrifice being unclear and Gamora not being in the presence of the soul gem, all of this is a pattern, and pattern implies purpose. This leads me to consider that these characters, when working together, have full control over all the stones, and the stones may refuse Thanos even if he wields them.

