From now until December 11, 2022 at 3:59pm PST / 6:59pm EST (23:59 UTC), some extra Pokémon are available in Tera Raid Dens, although which Pokémon you’ll find depends on which version you’re playing. If you’re playing Pokémon Scarlet, you’ll find Tyranitar more frequently than usual, while in Pokémon Violet, you’ll find Salamence more frequently than usual. They are available in 4-star and 5-star raids.
Although these remain version exclusives, these do provide an opportunity for players to join groups with players playing the opposite version to catch the version exclusive Pokémon. For instance, if you’re playing Pokémon Scarlet, you can find other players playing Violet that have Salamence raids up and join them more commonly, and vice versa.