Is there any more unrevealed Pokemon besides Darkrai Shaymin and Arceus?

As of the release of "Pokémon Brilliant Diamond and Shining Pearl" in November 2021, there are no officially announced unrevealed Pokémon besides Darkrai, Shaymin, and Arceus. However, it's worth noting that the Pokémon franchise constantly introduces new Pokémon in its upcoming games and media. New unrevealed Pokémon may be introduced in future games, anime series, or other official Pokémon releases.

To ensure you're up-to-date on the latest Pokémon news and information, I recommend visiting the official Pokémon website or following their official social media channels.