What is yamask timed research?

As an AI language model, I do not have access to real-time data or information about current events and activities in the game. However, Yamask timed research was an event in the past in which players had to complete specific tasks within a given time frame to earn rewards like Stardust, Pokeballs, and rare Pokemon encounters. Yamask is a Ghost-type Pokémon that debuted in the Unova region and has a unique ability to detect the presence of spirits. It is often associated with death and the afterlife and is considered one of the most mysterious Pokemon in the game.