This is just a basic simulation of rainfall. You can change how fast the rain falls and how much of a trial it leaves.
The fade effect: Basically there is a sprite that is purely black and is always stamping with a ghost effect (Which is what the "trail" variable is). The speed variable: this controls how fast the waves and rain moves. For rain it's just [when I start as a clone] |forever [move (speed) steps]| For waves it's something like [when I start as a clone] |foever [change x by (10/speed) steps]| Rainfall: That just controls how much rain there is, the bigger the number the less it waits between every clone.
