The first trailer for Avengers: Endgame Encore has arrived, and it changes one major line of dialogue in a very subtle way.

In the trailer, Tony Stark’s line from the 2019 original, “You mess with time, it tends to mess back,” has been changed to, “You mess with time, time tends to mess back.” In the film, Tony says this to Steve Rogers after Thanos and his army arrive in the present-day timeline.

This is a very minor change, but the line is fairly significant, considering it sums up one of the film’s rules of time travel. Could this be a hint about why Robert Downey Jr. is returning to play Doctor Doom in Avengers: Doomsday? Or is it just an alternate take of the same line that sounds better in a trailer than the original?

“That’s definitely for the trailer only because NO WAY they reshot that scene just to change one word,” thinks one fan.

“The V.O. dialogue is probably only for the trailer to emphasize “Encore and Doomsday’s” main theme (similar to what many other movie trailers do),” says someone else.

“This is definitely linked to Doomsday in some way and they want that line to be important,” predicts another fan.

“This is presumably (hopefully) just an edit to make the trailer more dramatic. There’s no way they’d actually re-dub lines to retroactively make Endgame a Doomsday setup movie… right?” says another person.

“Does this coincide with the time stone not being shown in any Doomsday promo? Or is that all just a coincidence?” questions someone else.

We’ll find out what it all means when Avengers: Endgame Encore arrives this September 25. Avengers: Doomsday, meanwhile, arrives on December 18.

In the meantime, check out our guide to all the upcoming Marvel movies and shows for everything else the MCU has in store.