Something very strange happened in Pokémon Go today at the conclusion of a scheduled community day event: A mysterious, never-before-seen Pokémon spawned in the game, leading to confusion and speculation about what it means for Niantic and The Pokémon Company’s mobile title.

In the Asia-Pacific region, at 3 p.m. in Japan, Pokémon Go’s community day event focused on the Pokémon Chikorita came to an end. Suddenly, the world of Pokémon Go was densely populated with a new type of Pokémon, one that looked like a white Ditto with a hexagonal nut for a head and a single eye at its center. When a player caught the new Pokémon — which appeared with the name “???” and a Combat Power (CP) rating of “???” — it would turn into a Ditto, typically an uncommon, harder-to-find Pokémon.

Many players initially wondered if the new Pokémon was some type of glitch, while others speculated that the creature may be the new species that’s supposed to make its debut in Pokémon: Let’s Go for Nintendo Switch.

The addition of the new mystery Pokémon was uncovered earlier this week, thanks to the data miner known as “Chrales.” They uncovered what they thought at the time was information on Kecleon, a Gen 3 Pokémon that hasn’t appeared in Pokémon Go yet.

The new creature seemingly has a Pokedex number of 891, Chrales noted. That’s unusual, given that the current highest Pokedex entry is Zeraora at 807. It’s also interesting that the new Pokémon already has standard and shiny forms.

Some players are now reporting that Kecleon is also appearing in their games, though that Pokémon’s behavior is similar to the new, still unnamed Pokémon. Kecleon caught by players simply turn into Ditto.

Something’s going on in Pokémon Go right now, but it’s not exactly clear what it is. It could be another herald of forthcoming Gen 4 Pokémon, or simply a way to drum up enthusiasm (and pre-orders) for Pokémon: Let’s Go, Pikachu! and Pokémon: Let’s Go, Eevee!, which come to Nintendo Switch in November.