Astonish is a Ghost-type move with 30 power and 100% accuracy. It has a 30% chance of causing the target to flinch, which can prevent the target from attacking during that turn. Despite its relatively low base power, Astonish can be useful due to its flinch chance, particularly when used by faster Pokémon. This move has seen use in early stages of the game or on Pokémon that benefit from additional status effects. Additionally, Astonish has the benefit of being effective against Ghost-type opponents, which can add strategic value in certain matchups.