Classic FFXI community

Some equipment and monsters change behavior depending on the Time of Day.

Game Term Hours Affects
Daytime 06:00-18:00 Daylight Dagger, Arco De Velocidad, Fenrir items
Nighttime 18:00-06:00 Ninja Artifact Armor, Nightmare Sword, Fenrir items, Giant Bats spawn in outdoor areas, Diurnal mobs go to sleep
Dusk to dawn 17:00-07:00 Ninja Artifact Armor +1
? 04:00-06:00
Dawn 06:00-07:00
? 07:00-17:00
Dusk 17:00-18:00 Verification Needed Lovers in the Dusk
Evening 18:00-20:00
? 20:00-04:00 Undead spawn in outdoor areas

In-game dawn and dusk are different from their real-life counterparts in that the in-game ones are considered part of daytime rather than nighttime. (According to Wikipedia, dusk refers to a time shortly after sunset.)