There have been numerous "leaks" for Avengers 4.
However, this leak, which offers a full description of the trailer, seems most possible. Here it is, with my full analysis of it.
The trailer starts off showing the damaged Infinity Gauntlet in a field on the farm planet. As the camera focuses in on the Gauntlet, we hear Tony’s voice: “We were destined to lose.” Epic music score starts The Quinjet is shown landing in a Wakandan wasteland as we hear Steve Rogers say: “We have come so far.” Tony and Nebula step off the jet as the remaining Avengers approach. Steve has a look of relief and says: “Tony”. Tony, seemingly defeated, shakes his head and gives a friendly smirk back to Cap. Marvel Studios Logo appears
This disproves the notion that it starts five years after Infinity War, as Tony comes back right after all the destruction. Thankfully, we now see the reunion between Tony and Cap.
We get a glimpse of the Battle of New York from 2012 Avengers. Loki is shown looking shocked and baffled as he is on top of the Stark tower. There is a flash of a blue light as the camera pans back. (Cuts to black) Next we see the Wakandan throne with M’Baku at the helm. He’s surrounded by his new kingsguard. (A mix of the hill tribe and Dora Milaje). Shuri and Banner are seen working on a new project in the lab. Black Widow, in full gear, is in Hawkeye’s family home from Age of Ultron. Basically everything is thrown all over the place and broken. Nat is studying some type of map with multiple photos and locations on it. A quick shot of Thanos is shown with a long sword, walking down an alleyway in New York City. The next shot is a dark hooded figure with glowing eyes, aiming a bow and arrow before shooting towards the camera.
So, we see that time-travel is happening, which we all kinda knew. The hood guy is obviously Hawkeye.
(1-2 visuals of the Quantum Realm) Scott Lang (no suit) is shown running through a park dodging explosions. (Shot of Space) Thor and Valkyrie are aboard a Kree ship. Thor says: “If the stories are true, you’re our universe’s last hope. If such a thing even exists anymore”. The next shot is an older, determined Tony Stark walking through the new SHIELD HQ’s (Avengers Facility in upstate New York). He’s in full SHIELD attire and carrying an orange briefcase. Banner (wearing spandex) is seen running from something, looking terrified. The next shot is Ant-Man appearing out of a flash of light and landing in a desolate place. We see it from his point of view from inside his helmet. He looks left to right and to his left again and says: “What in the-“.
This may actually help the theory of it starting in the future, because of the older Tony Stark in SHIELD attire. Also, it shows that Ant-Man may have wound up in a time-vortex and waking up in the future.
(Camera focuses on Vormir and its stars) Next, a shot of Rocket and Nebula modifying some new weapons in the lab. Rocket says “When can we try this bad boy out?” They both smile at eachother and fist-bump. We get our first glimpse of Iron Man in his red and gold nanotech armor. Hulk falls from the sky and lands in front of him. Thanos, in full armor, smiles. Hulk smiles back. The next shot is in Japan. War Machine, Nat, and Steve (in their full Avengers gear) are surrounded by The Yakuza. Hawkeye (Ronin) walks through everybody from behind them and approaches the Avengers. There’s an intense exchange of looks between Clint and Natasha (Next shot is at the Sanctum) Wong is communicating with Dr. Strange’s soul via portal. (Cuts to black) Grey haired Tony Stark and Ant-Man are in a post-apocalyptic NYC. The screen flashes back and forth multiple times through multiple scenes.
This might prove the soul stone theory with Doctor Strange.
We see Captain Marvel floating with her fists on fire and her eyes lit up. Thanos in the soul stone with young Gamora screaming at him Loki and Thor fighting off Chitauri together. And Tony handing Steve a brand new shield in the Wakandan throne room. (Cuts back to Tony and Scott) Tony opens the orange briefcase as Scott hands him an illuminated bracelet. Tony asks: “How?… Is this even possible?” (Iron Man and Ant-Man are shown travelling through the Quantum Realm. Tony and Scott are back in the battle of New York from 2012. The final shot before the title reveal is an Infinity Stone disappearing from Thanos’ damaged gauntlet. He abruptly gets up and puts on his armor. His face goes from extremely infuriated to a menacing smile.
A new shield sounds awesome, first of all. The stone disappearing may be a result of time-travel. The bracelet may be a device for time-travel.
Sounds way more likely than "The Last Avenger".
The Hulk is training at the new SHIELD facility with Black Widow and Steve. Steve notices that Hulk has been training non-stop as of late, so he asks why. Hulk responds in Banner’s normal voice with: “My rematch is coming real soon, I can feel it!”
Cheesy line, but perfect for who is apparently Professor Hulk!
Could this be real? What do you think? Comment!