Warner Bros. and Legendary Entertainment have been working hard to build their ever-growing cinematic MonsterVerse. Michael Dougherty, director of the upcoming Godzilla: King of the Monsters, recently teased an important connection between this new film and the original 1954 Godzilla. On Twitter, Dougherty marked the film’s 41st day of shooting with an image of the Oxygen Destroyer.

This weapon, created by Dr. Daisuke Serizawa (Akihiko Hirata), initially appeared in the original Godzilla. Following Tokyo’s destruction, Dr. Serizawa killed the original Godzilla and himself with the dangerous device. Given that Dr. Serizawa’s death was supposed to ensure no one ever recreated this device, how it relates to this new film is a true mystery.

“The new story follows the heroic efforts of the crypto-zoological agency Monarch as its members face off against a battery of god-sized monsters, including the mighty Godzilla, who collides with Mothra, Rodan, and his ultimate nemesis, the three-headed King Ghidorah. When these ancient super-species — thought to be mere myths — rise again, they all vie for supremacy, leaving humanity’s very existence hanging in the balance,” reads the film’s official synopsis.

Godzilla was originally released in Japan as Gojira in 1954, followed by the Americanized version Godzilla, King of the Monsters. As of now, it remains unknown what role the Oxygen Destroyer will play in Dougherty’s film. Despite going by roughly the same name, the addition of the other three kaiju confirms that the movie is not a recreation. The Oxygen Destroyer could easily play a similar role, or simply be a nostalgic Easter egg for fans.

Godzilla King of the Monsters stars Vera Farmiga, Ken Watanabe, Sally Hawkins, Kyle Chandler, Millie Bobby Brown, Bradley Whitford, Thomas Middleditch, Charles Dance, O’Shea Jackson Jr., Aisha Hinds and Zhang Ziyi. The film is debuting in theaters on March 22, 2019.