Godzilla has squared off with all sorts of terrifying kaiju over the years, but perhaps none more powerful than the three-headed King Ghidorah, a.k.a. Monster Zero. Though the golden dragon has had a couple different backstories over the different iterations of the Godzilla franchise, he’s best known as an invader from outer space, and he usually trashes the Earth at the behest of some malicious aliens. However, a new teaser suggests that King Ghidorah will have a different origin in Legendary’s new Godzilla series.

The official Kong: Skull Island Twitter account tweeted a timeline of the shared, kaiju-filled cinematic universe on Wednesday. In 1991, at the Isla De Mona in the Carribean, scientists from the monster-studying group MONARCH created a quarantine zone around a volcano. In the original Rodan movie, the giant Pterodactyl comes from a volcano. Then, in 2009, in China’s Yunnan province, MONARCH scientists found a megalithic temple with a giant cocoon inside. A “quickening heartbeat” is detected. Sure sounds like Mothra — and it might suggest we’re not going to see the kaiju’s caterpillar form.

There are also event pertaining to King Kong. In 1995, Houston Brooks (Corey Hawkins in Skull Island) and his son, Aaron, return to Kong’s homeland for an off-the-books mission to find out what happened to the giant ape since the 1973 mission that made up the first Kong film in the series. In 2012, Houston receives a coded message from Aaron containing “dramatic new information about Kong and his role on the island.”

Those events were highlighted or teased in previous tweets, but the main event in Wednesday’s video is a 2016 discovery, titled “Monster Zero.”

When MONARCH discover an extraordinary superspecies sealed beneath the Antarctic ice sheet, Dr. Vivienne Grahm leads the effort to build a convert containment and research facility around the dormant creature. Her classified field notes contain a mysterious footnote: “The devil has tree heads.”

Clearly, this is King Ghidorah. But, it doesn’t seem he’ll be descending from outer space in the upcoming Godzilla movie, which will feature the Big G, Mothra, Rodan, and Ghidorah. Maybe he’s still an alien — he’s just been on Earth (and on ice) for a long, long time.

Godzilla: King of the Monsters will stomp into theaters on March 22, 2019.

Photos via Toho