The upcoming ★7 Tera Raid in Pokemon Scarlet & Violet will feature Decidueye, the ultimate form of the Grass starter in Pokemon Sun & Moon.
According the the official Japanese Twitter of Pokemon, Decidueye in the ★7 raid will boast a Flying tera-type, which is weak to Electric-, Ice-, and Rock-type moves. However, Rock Pokemons will have to be careful as Decidueye, fundamentally a Grass/Ghost-type Pokemon, will have Grass moves that could pack a punch on Rock-types.
The event will occur in two different sessions:
Session 1: March 17 at 08:00 AM (GMT+8) until March 20 at 07:59 AM (GMT+8)
Session 2: March 24 at 08:00 AM (GMT+8) until March 27 at 07:59 AM (GMT+8)