In this scenario, the final battle of Infinity War (the one in Wakanda) gets a larger new cast of characters.
All the heroes who were present for that fight (Captain America, Black Panther, Bucky, Vision, Black Widow, Bruce Banner w/ Hulkbuster, Scarlet Witch, War Machine, Falcon etc) and the Wakandan army are there. So are the team who were fighting on Titan (Iron Man, Spider-Man, Doctor Strange and the Guardians of the Galaxy). And so are Thor, Rocket and Groot. Throw in Ant-Man and Hawkeye for good measure.
This time, there'll be an assault from a much larger army.
Thanos w/ the Power Gem only, the Black Order, the Outrider army, the Chitauri army, and Ultron with his drone army will all be attacking at the same time.
How does this huge fight go down?