just rummaging through the quest folder for kith, and found this in 20250.pl. looks likes its based off an NPC spawning
	Code:
	# kithicor night and day checker
#Angelox's reasoning :)
sub EVENT_SPAWN { 
quest::settimer("kithdaynight",10);
if ($zonetime < 800 || $zonetime > 1999) {
	quest::spawn_condition($zonesn, 2,0); #live are 2
	quest::spawn_condition($zonesn, 1,1); #undead are 1
}
else {
	quest::spawn_condition($zonesn,2,1); #live are 2
	quest::spawn_condition($zonesn,1,0); #undead are 1
}
 }
sub EVENT_TIMER {
if ($zonetime < 800 || $zonetime > 1999) {
	quest::spawn_condition($zonesn, 2,0); #live are 2
	quest::spawn_condition($zonesn, 1,1); #undead are 1
}
else {
	quest::spawn_condition($zonesn,2,1); #live are 2
	quest::spawn_condition($zonesn,1,0); #undead are 1
}
 }