Note: Potential spoilers follow for The Avengers: Infinity War.
A new look at Thor's new hammer for The Avengers: Infinity War lands online via a pic of merchandise.
Interestingly enough, the packaging also features Thor minus his eye patch from Thor: Ragnarok!
Regarding Thor's new hammer, it might be Jarnbjorn, the Dwarven-forged battle axe from the comics.
Here is another potential spoiler:
It's possible that when Thor runs into the Guardians of the Galaxy in Avengers: Infinity War, he tells them what happened with Thanos (post-credit scene from Thor: Ragnarok). Thor and the Guardians then go to make/find Thor a new hammer with Groot literally lending a hand. The above merchandise image and even the Avengers: Infinity War LEGO set seems to indicate that Groot provides Thor the handle for his new axe. It's also thought that Peter Dinklage plays the dwarf that creates Thor's new hammer in Avengers: Infinity War. So assuming this is correct, Thor and the Guardians of the Galaxy go on a side mission to create Thor's new weapon prior to meeting up with the Avengers and battling Thanos.
An unprecedented cinematic journey ten years in the making and spanning the entire Marvel Cinematic Universe, Marvel Studios’ “Avengers: Infinity War” brings to the screen the ultimate, deadliest showdown of all time. The Avengers and their Super Hero allies must be willing to sacrifice all in an attempt to defeat the powerful Thanos before his blitz of devastation and ruin puts an end to the universe.
Anthony and Joe Russo direct the film, which is produced by Kevin Feige. Louis D’Esposito, Victoria Alonso, Michael Grillo and Stan Lee are the executive producers. Christopher Markus & Stephen McFeely wrote the screenplay. “Avengers: Infinity War” releases in U.S. theaters on May 4, 2018.