Moon Twilight Flash was an attack used by Sailor Moon in the manga, video games, and Pretty Guardian Sailor Moon.
Manga
Sailor Moon used the gem in her tiara to reflect moonlight at the enemy. This attack was first used in Volume 01, Act 04, when Sailor Moon received a new tiara (in place of the one which had burned up while attacking Jadeite) and used its powers to destroy Nephrite's shadow.
Video Games
Sailor Moon also used this attack in the video games. The attack was performed the same way it was in the PGSM
Pretty Guardian Sailor Moon
This was Sailor Moon's third attack, which appears in Act 02. Sailor Moon's brooch begins to glow, and her Moonlight Stick appears. She shouts, "Moon Twilight Flash!" and splits into three colors. These three colors spin around, eventually forming back into one. Energy blasts forth from her wand, and targets the opponent.
thumb|300px|right|Twilight Flash in PGSM