How do I make weather effects?

From OHRRPGCE-Wiki

For example, let's say "Rain"

Every map has three layers. Layer 0 and layer 1 go underneath the hero and NPCs. Layer 2 goes over the top of the hero and NPCs, and is ideal for making weather effects like rain (or snow)

First, you need to go into the Maptile Editor and make an animating maptile that looks like rain falling.
Rain tiles in the maptile editor

Then go back to the Map Editor.

To enable layers on your map, press CTRL+L and turn on the layers.
add layers with the + button!
Press PageUp and PageDown to select which layer you are editing
Check which layer you're on here.
When you put your rain tile in layer 2, the other layers will be visible between the raindrops
Rain on layer 2!

To fill the map layer with rain tiles quickly, use CTRL+F to fill the screen, or CTRL+R to replace all tiles with the selected one.

Press 1 (for singular tiles) or CTRL+1 to animate all your rain maptiles. Read more about animating map tiles here!