This is incredibly easy. I dont see why everyone keeps asking for a script.
Step 1: Create a Common Event for your time triggers.
Step 2: Create a switch that will activate the common event. (Ex: Switch 001: Daynight)
-----------------------------------------------------------------------
First create an event in the map where the game starts. Set it to Auto Start then put the following events in:
Switch Operation: 001: Daynight is ON
Erase Event
Now that that is done, go into the common event and enter the following:
[Loop]
Tint screen: -87, -87, -87, transition frames: 40
Wait: 999 frames.
Tint Screen: 0, 0, 0, transition frames: 40
[End Loop]
Your first command will be to loop the event over and over so that it continues through your game.
Your second command is going to be to tint the screen. Take all the colors down to -87ish. That will be sufficient for night.
Your third command will be to wait 999 frames. This is plenty of time for day and for night.
Your fourth command will be to tint the screen again. Take all colors back to 0 each. This will return the tint to the normal screen brightness.
----------------------------------------------------------------------------------
If you want certain events to happen during day or night, then you do this:
[Loop]
Trigger Operation: 002: Daylight is OFF
Tint screen: -87, -87, -87, transition frames: 40
Trigger Operation: 002: Nighttime is ON
Wait: 999 frames.
Trigger Operation: 002: Daylight is ON
Tint Screen: 0, 0, 0, transition frames: 40
Trigger Operation: 002: Nighttime is OFF
[End Loop]
This way, you can set certain events to only be active when the nighttime or daytime switches are active, therefore allowing you to make events corresponding to day and night.
This also works if you want to create a werewolf system for your character. (*hint hint*)