The next Pokemon Scarlet and Violet Tera Raid will involve Blissey. If people check the in-game announcements, there’s one noting the event will start on March 24, 2023. This will be a chance to not only get the character with different Tera Types, but also to get more Tera Shards and Exp. items.
The Blissey Tera Raids in Pokemon Scarlet and Violet will be five-star ones. This means people won’t need to have finished the game or post-game activities to access them. With the rewards, it isn’t guaranteed that someone will get more Tera Shards than usual. However, the wording in the announcement does mention “bonus Exp. candies” regardless. However, if someone’s Blissey raid does involve extra Tera Shards, it means they will be from multiple types, rather than just the type that Blissey is.
This also means the Blissey event will be running at the same time as the second part of the Decidueye Tera Raid. The second part of that will take place March 24-27, 2023. (The first happened March 17-20, 2023.) That involved a seven-star one with a mark that would be a Flying Tera Type.
Pokemon Scarlet and Violet are available for the Nintendo Switch, and the Blissey Tera Raids run March 24-26, 2023.