Now that Batman v Superman: Dawn of Justice is readily available on Blu-ray and DVD, fans are still discovering new details in this superhero adventure. Earlier this month, set photographer Clay Enos and director Zack Snyder confirmed the presence of an obscure Easter Egg, with the shape formed by a broken pane of glass resembling the Canadian province of Ontario, where Superman co-creator Joe Shuster was born. Today we have confirmation of a new and equally-obscure Easter Egg, although this one sheds new light on the actual story.

A Twitter user reached out to Clay Enos this weekend, after a photo surfaced that revealed the Kryptonite canisters were marked with Pb, which is the periodic table symbol for lead. These canisters were shown being made by by Bruce Wayne (Ben Affleck) during a training montage, and during one quick close-up shot, the "Pb" letters can be seen. When asked by a fan if the Pb signifies lead, Clay Enos confirmed it did signify lead, stating that, "nothing happens by accident in Zack's movies."

As longtime comic book fans know, Superman's X-ray vision cannot see through lead, which was also addressed earlier in the movie as well. The wheelchair used by Scoot McNairy's character Wallace Keefe was lined with lead and filled with explosives, which is why Henry Cavill's Superman could not see the explosives used in the Senate bombing, orchestrated by Lex Luthor (Jesse Eisenberg). This Easter Egg shows that Bruce Wayne has been doing his research on Superman, which was also teased in a comic book released just before Batman v Superman hits theaters.

While Superman's inability to see through lead is widely known by comic book fans, it isn't exactly common knowledge in the DCEU. Back in February, a series of four comic book issues debuted in boxes of General Mills cereal, which revealed that Ben Affleck's Batman has been doing research into Superman's weaknesses. The comic book entitled "Field Trip" featured a group of thieves wielding Kryptonian weaponry infiltrating the Wayne Industries headquarters, while a school field trip is in session. A young girl named Zoe asks Bruce Wayne himself why Superman can't see there are hostages in the building, Bruce reveals that the entire building has been lead-lined, so Superman can't see inside.

Batman v Superman: Dawn of Justice earned $873.2 million worldwide at the box office, but it wasn't well-received by the nation's critics, with just a 27% rating on Rotten Tomatoes. All of the main Batman v Superman are returning for Justice League, which is currently filming in the U.K. and set for release on November 17, 2017. Take a look at the tweets below that confirm the new Easter Egg for Batman v Superman: Dawn of Justice.