Merlin SDK:
When creating maps in the SDK, you can specify lighting and sky presets to use at different times of day. In the VTT, Merlin interpolates between these presets while moving the sun's position.
Merlin also has default sky presets it will try to use if none have been set.
You can also link custom blueprints to an event that runs whenever the time of day is changed, so you can create time-dependent scripts. For example: ambient noise in a forest that should sound different depending on whether it's day or night. Another example: in the Medieval Tavern demo map, we use this to change the level of fog during day or night.
Merlin VTT:
Control panel that lets the GM set the current time of day, and whether it should actively change.
Set to noon/night/dawn/dusk and total darkness presets, and a dial to set to a more specific time.
Tick time forwards at variable speed or pause completely.
Day Time Control Panel