Dusk Ball

Used in battle : Attempts to catch a wild Pokémon. If it's currently nighttime or the wild Pokémon was encountered while walking in a cave, this ball has a catch rate of 3.5×. Otherwise, it has a catch rate of 1×. If used in a trainer battle, nothing happens and the ball is lost.

“A somewhat different Poké Ball that makes it easier to catch wild Pokémon at night or in dark places like caves.”