Avengers: Infinity War Directors Tease Mysterious New Prop Video

Avengers: Infinity War directors The Russo Bros. (Captain America: The Winter Soldier & Civil War) have posted a new video teasing a prop being made for Infinity War using a 3D printing process called stereolithography. 

We have NO idea what it is, but we know fans will be discussing! Leave your best guess in the comments! 

 The Russos have been (teasing? Trolling?) fans like this throughout Infinity War's production. The directing duo previously tweeted a yellow blob as a "first look" at Infinity War, simultaneously playing on the current trend of superhero movie filmmakers using social media as a promotional channel, while also refraining from any actual big reveals